diff --git a/build.gradle b/build.gradle
index a7913a1..b225153 100644
--- a/build.gradle
+++ b/build.gradle
@@ -44,7 +44,7 @@ ext {
     cyfaceEnergySettingsVersion = "0.0.0" // Automatically overwritten by CI
 
     // Cyface dependencies
-    cyfaceUtilsVersion = "3.3.7"
+    cyfaceUtilsVersion = "3.5.0"
 
     // Android SDK versions
     minSdkVersion = 21 // device support
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/ProblematicManufacturerWarningDialog.kt b/energy_settings/src/main/java/de/cyface/energy_settings/ProblematicManufacturerWarningDialog.kt
deleted file mode 100644
index 9fe9ece..0000000
--- a/energy_settings/src/main/java/de/cyface/energy_settings/ProblematicManufacturerWarningDialog.kt
+++ /dev/null
@@ -1,451 +0,0 @@
-/*
- * Copyright 2019-2023 Cyface GmbH
- *
- * This file is part of the Cyface Energy Settings for Android.
- *
- * The Cyface Energy Settings for Android is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * The Cyface Energy Settings for Android is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with the Cyface Energy Settings for Android. If not, see <http://www.gnu.org/licenses/>.
- */
-package de.cyface.energy_settings
-
-import android.app.Activity
-import android.app.AlertDialog
-import android.app.Dialog
-import android.content.ComponentName
-import android.content.Context
-import android.content.Intent
-import android.content.pm.PackageManager
-import android.os.Build
-import android.os.Bundle
-import android.util.Log
-import androidx.preference.PreferenceManager
-import com.afollestad.materialdialogs.MaterialDialog
-import de.cyface.energy_settings.Constants.TAG
-import de.cyface.energy_settings.GnssDisabledWarningDialog.Companion.create
-import de.cyface.energy_settings.ProblematicManufacturerWarningDialog.Companion.create
-import java.util.*
-import kotlin.collections.LinkedHashMap
-
-/**
- * Dialog to show a warning when a phone manufacturer is identified which allows to prevent background tracking
- * by manufacturer-specific settings.
- *
- * This dialog is customized by searching for a match in a known list of manufacturer-specific energy settings pages.
- * If a match is found the required steps to adjust the settings are shown and the setting page is accessible via a
- * dialog button. Else, a generic text is shown in the dialog to help the user finding the energy settings by itself.
- *
- * This dialog also contains a button which allows the user to disable the auto-popup of this dialog.
- * This preference is not respected when the user requests guidance explicitly.
- *
- * Two implementation are available:
- *
- * 1. As `DialogFragment`. Use the constructor and use the dialog. Calls [onCreateDialog] internally.
- * 2. As [MaterialDialog]. Use the static [create] method which returns the dialog.
- *
- * @author Armin Schnabel
- * @version 2.1.0
- * @since 1.0.0
- *
- * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated template.
- */
-internal class ProblematicManufacturerWarningDialog(private val recipientEmail: String) : EnergySettingDialog() {
-
-  override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
-
-    // Generate dialog
-    val builder = AlertDialog.Builder(activity)
-    builder.setTitle(titleRes)
-
-    // Allow the user to express its preference to disable auto-popup of this dialog
-    builder.setNegativeButton(negativeButtonRes) { _, _ ->
-      onNegativeButtonCall(context)
-    }
-
-    // Show Sony STAMINA specific dialog (no manufacturer specific intent name known yet)
-    val messageRes = if (isSony()) sonyStaminaMessageRes else genericMessageRes
-
-    // Context-less scenario
-    val context = context
-    if (context == null) {
-      Log.w(TAG, "No ProblematicManufacturerWarningDialog shown, context is null.")
-      builder.setMessage(messageRes)
-      return builder.create()
-    }
-
-    // If a device specific settings page is found, add a button to open it directly
-    val deviceSpecificIntent = getDeviceSpecificIntent(context)
-    if (deviceSpecificIntent != null) {
-
-      // [STAD-492] Since 2021 Huawei started to deny opening the Huawei "App Launch" setting via intent.
-      val unreachableSetting = deviceSpecificIntent.key.component!!.className.equals("com.huawei.systemmanager.startupmgr.ui.StartupNormalAppListActivity")
-      return if (unreachableSetting) {
-          builder.setMessage(deviceSpecificIntent.value) // Use the message for the identified intent
-          builder.setPositiveButton(feedbackButtonRes) { _, _ ->
-            startActivity(Intent.createChooser(intent(context, recipientEmail), getString(chooseEmailAppRes)))
-          }
-        builder.create()
-      } else {
-          val settingsIntent = deviceSpecificIntent.key
-          builder.setMessage(deviceSpecificIntent.value)
-          builder.setPositiveButton(openSettingsButtonRes) { _, _ -> startActivity(settingsIntent) }
-        builder.create()
-      }
-    } else {
-
-      // Generate a feedback button
-      builder.setPositiveButton(feedbackButtonRes) { _, _ ->
-        startActivity(Intent.createChooser(intent(context, recipientEmail), getString(chooseEmailAppRes)))
-      }
-
-      builder.setMessage(messageRes)
-      return builder.create()
-    }
-  }
-
-  companion object {
-    /**
-     * The resource pointing to the text used as title.
-     */
-    private val titleRes = R.string.dialog_problematic_manufacturer_warning_title
-    /**
-     * The resource pointing to the text of the generic dialog which is shown when no manufacturer-specific
-     * energy setting page is found
-     */
-    private var genericMessageRes = R.string.dialog_manufacturer_warning_generic
-    /**
-     * The resource pointing to the text of the dialog which is shown when no manufacturer-specific
-     * energy setting page is found but a sony device is detected
-     */
-    private val sonyStaminaMessageRes = R.string.dialog_manufacturer_warning_sony_stamina
-    /**
-     * The resource pointing to the text used as positive button which opens the settings.
-     */
-    private val openSettingsButtonRes = R.string.dialog_button_open_settings
-    /**
-     * The resource pointing to the text used as positive button which opens a feedback email template.
-     */
-    private val feedbackButtonRes = R.string.dialog_button_help
-    /**
-     * The resource pointing to the text used as negative button which stores the "don't show again" preference.
-     */
-    private val negativeButtonRes = R.string.dialog_button_do_not_show_again
-
-    private fun isSony(): Boolean {
-      return Build.MANUFACTURER.lowercase(Locale.ROOT) == Constants.MANUFACTURER_SONY
-    }
-
-    /**
-     * Saves the user's preference to disable auto-popup of this dialog
-     */
-    private fun onNegativeButtonCall(context: Context?) {
-      val preferences = PreferenceManager.getDefaultSharedPreferences(context!!)
-      preferences.edit().putBoolean(Constants.PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY, true).apply()
-    }
-
-    /**
-     * Alternative, `FragmentManager`-less implementation.
-     *
-     * @param activity Required to show the dialog
-     */
-    fun create(activity: Activity, recipientEmail: String): MaterialDialog {
-
-      // Generate dialog
-      val dialog = MaterialDialog(activity, DIALOG_BEHAVIOUR)
-      dialog.title(titleRes, null)
-
-      // Allow the user to express its preference to disable auto-popup of this dialog
-      dialog.negativeButton(negativeButtonRes) {
-        onNegativeButtonCall(activity.applicationContext)
-      }
-
-      // Show Sony STAMINA specific dialog (no manufacturer specific intent name known yet)
-      val messageRes = if (isSony()) sonyStaminaMessageRes else genericMessageRes
-
-      // Context-less scenario
-      val context = activity.applicationContext
-      if (context == null) {
-        Log.w(TAG, "No ProblematicManufacturerWarningDialog shown, context is null.")
-        dialog.message(messageRes)
-        return dialog
-      }
-
-      // If a device specific settings page is found, add a button to open it directly
-      val deviceSpecificIntent = getDeviceSpecificIntent(context)
-      if (deviceSpecificIntent != null) {
-
-        // [STAD-492] Since 2021 Huawei started to deny opening the Huawei "App Launch" setting via intent.
-        val unreachable = deviceSpecificIntent.key.component!!.className.equals("com.huawei.systemmanager.startupmgr.ui.StartupNormalAppListActivity")
-        return if (unreachable) {
-          dialog.positiveButton(feedbackButtonRes) {
-            activity.startActivity(
-              Intent.createChooser(
-                intent(context, recipientEmail),
-                context.getString(chooseEmailAppRes)
-              )
-            )
-          }
-          dialog.message(deviceSpecificIntent.value) // Use the message for the identified intent
-          dialog
-        } else {
-          val settingsIntent = deviceSpecificIntent.key
-          dialog.positiveButton(openSettingsButtonRes) { activity.startActivity(settingsIntent) }
-          dialog.message(deviceSpecificIntent.value)
-          dialog
-        }
-      } else {
-
-        // Generate a feedback button
-        dialog.positiveButton(feedbackButtonRes) {
-          activity.startActivity(
-            Intent.createChooser(
-              intent(context, recipientEmail),
-              context.getString(chooseEmailAppRes)
-            )
-          )
-        }
-
-        dialog.message(messageRes)
-        return dialog
-      }
-    }
-
-    /**
-     * Searches for a match of a list of known device-specific energy setting pages.
-     *
-     * @param context The [Context] to check if the intent is resolvable on this device
-     * @return The intent to open the settings page and the resource id of the message string which describes what to do
-     * on the settings page. Returns `Null` if no intent was resolved. Always returns the first match,
-     * which means the intent which was added in a later Android version if there are multiple matches.
-     */
-    private fun getDeviceSpecificIntent(context: Context): Map.Entry<Intent, Int>? {
-      // (!) This needs to be an ordered map or else StartupAppControlActivity might be returned in favor
-      // of StartupNormalAppListActivity if both exist which leads to an error [MOV-989]
-      val intentMap: MutableMap<Intent, Int> = LinkedHashMap()
-
-      /*
-       * Huawei/Honor
-       * - EMUI OS (https://de.wikipedia.org/wiki/EMUI#Versionen)
-       *******************************************************************************************/
-
-      // "App-Start", e.g. EMUI 9, 10
-
-      // [STAD-492] Since 2021 Huawei started to deny opening the Huawei "App Launch" setting via intent.
-      // A SecurityException is thrown. I.e. the user now has to navigate on it's own to the settings.
-      // On our test devices this cannot be reproduced but we see this frequently now in the Play Console.
-      // But as we only see the crashes in Android 10, we leave `< Build.VERSION_CODES.Q` as it is.
-      // We need to leave both intents here, so that the correct text is shown in the dialog.
-      // We only disable the settings-button where `getDeviceSpecificIntent()` is called.
-
-      // [MOV-989] On EMUI 10.0.0 (e.g. our P smart 2019) it finds both:
-      // 1. StartupNormalAppListActivity (which works on new EMUI versions)
-      // 2. StartupAppControlActivity (which crashes on new EMUI even with USE_COMPONENT permission)
-      // This is why we need to keep the intents here in an ordered map with (1) earlier in the map
-      // This way always (1) is returned before (2)
-
-      // P20, EMUI 9, Android 9, 2019 - comment in https://stackoverflow.com/a/48641229/5815054
-      // when adding the permissions above does not work with the intent above
-      intentMap[Intent().setComponent(ComponentName("com.huawei.systemmanager",
-        "com.huawei.systemmanager.startupmgr.ui.StartupNormalAppListActivity"))] = R.string.dialog_manufacturer_warning_huawei_app_launch
-
-      // P20, EMUI 9, Android 9, 2018 - comment in https://stackoverflow.com/a/35220476/5815054
-      // [STAD-280] This check should not be necessary as `StartupNormalAppListActivity` should
-      // always be prioritised by the current code if both are found. However, on some Android 10
-      // devices it seems like this activity is still called. Thus, we completely disable it on Q+.
-      if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
-        intentMap[Intent().setComponent(ComponentName("com.huawei.systemmanager",
-                "com.huawei.systemmanager.appcontrol.activity.StartupAppControlActivity"))] = R.string.dialog_manufacturer_warning_huawei_app_launch
-      }
-
-      // "Protected Apps", EMUI <5, Android <7
-      intentMap[Intent().setComponent(ComponentName("com.huawei.systemmanager",
-        "com.huawei.systemmanager.optimize.process.ProtectActivity"))] = R.string.dialog_manufacturer_warning_huawei_protected_app
-
-      /*
-       * Samsung
-       * - One UI (https://de.wikipedia.org/wiki/One_UI)
-       * - TouchWiz (https://en.wikipedia.org/wiki/TouchWiz)
-       *******************************************************************************************/
-
-      // Android 7+, "Unmonitored Apps"
-      // - http://sleep.urbandroid.org/documentation/faq/alarms-sleep-tracking-dont-work/#sleeping-apps
-      // - Unable to test if this is necessary as we don't have a Samsung Android 7 device
-      intentMap[Intent().setComponent(ComponentName("com.samsung.android.lool",
-        "com.samsung.android.sm.ui.battery.BatteryActivity"))] = R.string.dialog_manufacturer_warning_samsung_device_care
-
-      // Android 5-6 - https://code.briarproject.org/briar/briar/issues/1100
-      // - tested: settings found and opened on Android 6.0.1 (office phone: S5 neo)
-      // - by default (our phone) this was off but people might have enabled both general and app-specific option
-      intentMap[Intent().setComponent(ComponentName("com.samsung.android.sm",
-        "com.samsung.android.sm.ui.battery.BatteryActivity"))] = R.string.dialog_manufacturer_warning_samsung_smart_manager
-
-      /*
-       * Xiaomi
-       * - MIUI (https://en.wikipedia.org/wiki/MIUI#Version_history)
-       *******************************************************************************************/
-
-      // Tested on Redmi Note 5 (Android 8.1, MIUI 10)
-      intentMap[Intent().setComponent(ComponentName("com.miui.securitycenter",
-        "com.miui.powercenter.PowerSettings"))] = R.string.dialog_manufacturer_warning_xiaomi_power_settings
-      intentMap[Intent().setComponent(ComponentName("com.miui.securitycenter",
-        "com.miui.permcenter.autostart.AutoStartManagementActivity"))] = R.string.dialog_manufacturer_warning_xiaomi_auto_start
-
-      // from https://github.com/dirkam/backgroundable-android
-      // Unsure if this is the correct dialog
-      intentMap[Intent("miui.intent.action.POWER_HIDE_MODE_APP_LIST").addCategory(Intent.CATEGORY_DEFAULT)] = R.string.dialog_manufacturer_warning_xiaomi_power_settings
-
-      // Unsure if this is the correct dialog
-      intentMap[Intent("miui.intent.action.OP_AUTO_START").addCategory(Intent.CATEGORY_DEFAULT)] = R.string.dialog_manufacturer_warning_xiaomi_auto_start
-
-      /*
-       * Other manufacturers
-       * - The following manufacturers seem to be as restrictive as Huawei etc. (see https://dontkillmyapp.com)
-       * - but we have no negative reports yet from such devices, nor can we test them.
-       * - For those reasons this part is uncommented but we keep this info here as it's some work to collect this
-       * data.
-       *******************************************************************************************/
-
-      /*
-       * HTC
-       * - Boost+ App https://www.htc.com/de/support/htc-one-a9s/howto/830580.html
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.htc.pitroad",
-       * "com.htc.pitroad.landingpage.activity.LandingPageActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *******************************************************************************************/
-
-      /*
-       * Oppo
-       *
-       * Might require the following permissions:
-       * From comment in https://stackoverflow.com/a/48641229/5815054 - required for
-       * com.coloros.safecenter/.startupapp.StartupAppListActivity
-       * <uses-permission android:name="oppo.permission.OPPO_COMPONENT_SAFE"/>
-       * From https://stackoverflow.com/a/51726040/5815054
-       * <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"/>
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.safecenter",
-       * "com.coloros.safecenter.permission.startup.StartupAppListActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * // From https://stackoverflow.com/a/51726040/5815054 and https://github.com/dirkam/backgroundable-android
-       * // Android >= 7 (ColorOS >= 3)
-       * if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.safecenter",
-       * "com.coloros.safecenter.startupapp.StartupAppListActivity")).setAction(Settings.
-       * / * VIOLATION WARNING: ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS * /
-       * ACTION_IGNORE_BATTERY_OPTIMIZATION_SETTINGS)
-       * .setData(Uri.parse("package:" + context.getPackageName())),
-       * R.string.dialog_manufacturer_warning_generic);
-       * }
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.oppo.safe",
-       * "com.oppo.safe.permission.startup.StartupAppListActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * // From https://stackoverflow.com/a/51726040/5815054
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.oppoguardelf",
-       * "com.coloros.powermanager.fuelgaue.PowerUsageModelActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.oppoguardelf",
-       * "com.coloros.powermanager.fuelgaue.PowerSaverModeActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.oppoguardelf",
-       * "com.coloros.powermanager.fuelgaue.PowerConsumptionActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      /*
-       * Asus
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.asus.mobilemanager",
-       * "com.asus.mobilemanager.MainActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * // From https://stackoverflow.com/a/51726040/5815054
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.asus.mobilemanager",
-       * "com.asus.mobilemanager.entry.FunctionActivity"))
-       * // From https://stackoverflow.com/a/49110392/5815054
-       * .setData(Uri.parse("mobilemanager://function/entry/AutoStart")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.asus.mobilemanager",
-       * "com.asus.mobilemanager.autostart.AutoStartActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      /*
-       * Letv
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.letv.android.letvsafe",
-       * "com.letv.android.letvsafe.AutobootManageActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      /*
-       * Meizu
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.meizu.safe",
-       * "com.meizu.safe.security.SHOW_APPSEC"))
-       * .addCategory(Intent.CATEGORY_DEFAULT).putExtra("packageName", BuildConfig.APPLICATION_ID),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      /*
-       * Vivo
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.iqoo.secure",
-       * "com.iqoo.secure.ui.phoneoptimize.AddWhiteListActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.vivo.permissionmanager",
-       * "com.vivo.permissionmanager.activity.BgStartUpManagerActivity")),
-       * R.string.dialog_manufacturer_warning_generic);
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.iqoo.secure",
-       * "com.iqoo.secure.ui.phoneoptimize.BgStartUpManager")),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      /*
-       * Dewav
-       * - https://stackoverflow.com/a/49110392/5815054
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.dewav.dwappmanager",
-       * "com.dewav.dwappmanager.memory.SmartClearupWhiteList")),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      /*
-       * Qmobile
-       * - from comment in https://stackoverflow.com/a/49110392/5815054
-       *
-       * intentMap.put(new Intent().setComponent(new ComponentName("com.dewav.dwappmanager",
-       * "com.dewav.dwappmanager.memory.SmartClearupWhiteList")),
-       * R.string.dialog_manufacturer_warning_generic);
-       */
-
-      // Search for a match in the list of known energy settings pages
-      // Return the first match. If not this leads to [MOV-989], see note above.
-      for(entry in intentMap.entries) {
-        if (context.packageManager.resolveActivity(entry.key,
-            PackageManager.MATCH_DEFAULT_ONLY) != null) {
-          return entry
-        }
-      }
-
-      return null
-    }
-  }
-}
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/TrackingSettings.kt b/energy_settings/src/main/java/de/cyface/energy_settings/TrackingSettings.kt
deleted file mode 100644
index 66ae5de..0000000
--- a/energy_settings/src/main/java/de/cyface/energy_settings/TrackingSettings.kt
+++ /dev/null
@@ -1,510 +0,0 @@
-/*
- * Copyright 2019-2022 Cyface GmbH
- *
- * This file is part of the Cyface Energy Settings for Android.
- *
- * The Cyface Energy Settings for Android is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * The Cyface Energy Settings for Android is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with the Cyface Energy Settings for Android. If not, see <http://www.gnu.org/licenses/>.
- */
-package de.cyface.energy_settings
-
-import android.app.Activity
-import android.app.ActivityManager
-import android.content.Context
-import android.content.Intent
-import android.content.pm.PackageManager
-import android.location.LocationManager
-import android.os.Build
-import android.os.PowerManager
-import android.util.Log
-import androidx.annotation.RequiresApi
-import androidx.fragment.app.Fragment
-import androidx.fragment.app.FragmentManager
-import androidx.preference.PreferenceManager
-import de.cyface.utils.Validate
-import java.util.Locale
-
-/**
- * Holds the API for this energy setting library.
- *
- * Offers checks and dialogs for energy settings required for background tracking.
- *
- * @author Armin Schnabel
- * @version 2.0.3
- * @since 1.0.0
- */
-object TrackingSettings {
-
-  /**
-   * Checks whether the energy safer mode is active *at this moment*.
-   *
-   * If this mode is active the GPS location service is disabled on most devices.
-   *
-   * API 28+
-   * - due to Android documentation GPS is only disabled starting with API 28 when the display is off
-   * - manufacturers can change this. On a Pixel 2 XL e.g. GPS is offline. On most other devices, too.
-   * - we explicitly check if this is the case on the device and only return true if GPS gets disabled
-   *
-   * API < 28
-   * - Some manufacturers implemented an own energy saving mode (e.g. on Honor 8, Android 7) which also kills GPS
-   * when this mode is active and the display disabled. Thus, we don't also don't allow energy safer mode on lower
-   * APIs.
-   *
-   * @param context The `Context` required to check the system settings
-   * @return `True` if an energy safer mode is currently active which very likely disables the GPS service
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun isEnergySaferActive(context: Context): Boolean {
-
-    val powerManager = context.getSystemService(Context.POWER_SERVICE) as PowerManager
-    val isInPowerSavingMode = powerManager.isPowerSaveMode
-
-    // On newer APIs we can check if the power safer mode actually kills location tracking in background
-    return if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) {
-      isInPowerSavingMode
-    } else isInPowerSavingMode
-      && powerManager.locationPowerSaveMode != PowerManager.LOCATION_MODE_FOREGROUND_ONLY
-      && powerManager.locationPowerSaveMode != PowerManager.LOCATION_MODE_NO_CHANGE
-  }
-
-  /**
-   * Checks whether background processing is restricted by the settings.
-   *
-   * If this mode is enabled, the background processing is paused when the app is in background or the display is off.
-   *
-   * This was tested on a Pixel 2 XL device. Here this setting is disabled by default.
-   * On other manufacturers, e.g. on Xiaomi's MIUI this setting is enabled by default.
-   *
-   * @param context The `Context` required to check the system settings
-   * @return `True` if the processing is restricted
-   */
-  @JvmStatic
-  @RequiresApi(api = Build.VERSION_CODES.P)
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun isBackgroundProcessingRestricted(context: Context): Boolean {
-
-    val activityManager = context.getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
-    return (activityManager.isBackgroundRestricted)
-  }
-
-  /**
-   * Checks whether a manufacturer was identified which implements manufacturer-specific energy settings known to
-   * prevent background tracking when set up wrong or even with the default settings.
-   *
-   * @return `True` if such a manufacturer is identified
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate", "SpellCheckingInspection") // Used by implementing app
-  val isProblematicManufacturer: Boolean
-    get() {
-
-      return when (Build.MANUFACTURER.lowercase(Locale.ROOT)) {
-        Constants.MANUFACTURER_HUAWEI, Constants.MANUFACTURER_HONOR, Constants.MANUFACTURER_SAMSUNG,
-        Constants.MANUFACTURER_XIAOMI, Constants.MANUFACTURER_SONY -> true
-        /* Sony STAMINA
-         * - On Android 8 we may be able to check if STAMINA is disabled completely according to:
-         * https://stackoverflow.com/a/50740898/5815054/, https://dontkillmyapp.com/sony
-         * Settings.Secure.getInt(context.getContentResolver(), "somc.stamina_mode", 0) > 0;
-         * - However, as this does not work on Android 6 we just show the warning to all SONY phones
-         */
-        /*
-         * Other manufacturers
-         * - The following manufacturers seem to be as restrictive as Huawei etc. (see
-         * https://dontkillmyapp.com)
-         * - but we have no negative reports yet from such devices, nor can we test them.
-         * - For those reasons this part is uncommented but we keep this info here as it's some work to collect
-         * this data.
-         *
-         * case MANUFACTURER_HTC:
-         * case MANUFACTURER_OPPO:
-         * case MANUFACTURER_ASUS:
-         * case MANUFACTURER_LETV:
-         * case MANUFACTURER_VIVO:
-         * case MANUFACTURER_MEIZU:
-         * case MANUFACTURER_DEWAV:
-         * case MANUFACTURER_QMOBILE:
-         */
-        else -> false
-      }
-    }
-
-  /**
-   * Checks whether GPS is enabled in the settings.
-   *
-   * @param context The `Context` required to check the system settings
-   * @return `True` if GPS is enabled
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun isGnssEnabled(context: Context): Boolean {
-
-    val manager = context.getSystemService(Context.LOCATION_SERVICE) as LocationManager
-    return manager.isProviderEnabled(LocationManager.GPS_PROVIDER)
-  }
-
-  /*
-   * Battery Optimization setting
-   *
-   * - Tests showed that this option should not be needed. (It also may sound scary to the user.)
-   * - Android settings explain that this setting is only needed if the was not Doze-optimized.
-   * - Our app should be Doze-optimized - which our tests indicated, too.
-   *
-   * else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M
-   * && powerManager != null && !powerManager.isIgnoringBatteryOptimizations(packageName)) {
-   *
-   * There are two native dialogs which can be popped up:
-   *
-   * 1) Request direct white-listing
-   * - this is not allowed in all cases and can end up in a denied play store release
-   * - this would required the following permissions:
-   * <uses-permission
-   * android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"/>
-   *
-   * 2) Open the settings page where the user hat to white-list the app himself
-   * final Intent intent = new Intent();
-   * intent.setAction(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS);
-   * intent.setData(Uri.parse("package:" + packageName));
-   * fragmentRoot.getContext().startActivity(intent);
-   * }
-   */
-
-  /**
-   * Shows a [EnergySaferWarningDialog] when [.isEnergySaferActive] is true.
-   *
-   * Checks [.isEnergySaferActive] before showing the dialog.
-   *
-   * @param context The `Context` required to check the system settings
-   * @param fragment The `Fragment` where the dialog should be shown
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
-  fun showEnergySaferWarningDialog(context: Context, fragment: Fragment): Boolean {
-
-    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isEnergySaferActive(context)) {
-      val fragmentManager = fragment.fragmentManager
-      Validate.notNull(fragmentManager)
-      val dialog = EnergySaferWarningDialog()
-      dialog.setTargetFragment(fragment, Constants.DIALOG_ENERGY_SAFER_WARNING_CODE)
-      dialog.show(fragmentManager!!, "ENERGY_SAFER_WARNING_DIALOG")
-      return true
-    }
-    return false
-  }
-
-  /**
-   * Shows a [EnergySaferWarningDialog] when [.isEnergySaferActive] is true.
-   *
-   * Checks [.isEnergySaferActive] before showing the dialog.
-   *
-   * @param activity Required to show the dialog
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun showEnergySaferWarningDialog(activity: Activity?): Boolean {
-
-    if (activity == null || activity.isFinishing) {
-      Log.w(Constants.TAG, "showEnergySaferWarningDialog: aborted, activity is null")
-      return false
-    }
-
-    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isEnergySaferActive(activity.applicationContext)) {
-      EnergySaferWarningDialog.create(activity).show()
-      return true
-    }
-    return false
-  }
-
-  /**
-   * Shows a [BackgroundProcessingRestrictionWarningDialog] when
-   * [.isBackgroundProcessingRestricted] is true.
-   *
-   * Checks [.isBackgroundProcessingRestricted] before showing the dialog.
-   *
-   * @param context The `Context` required to check the system settings
-   * @param fragment The `Fragment` where the dialog should be shown
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
-  fun showRestrictedBackgroundProcessingWarningDialog(context: Context, fragment: Fragment): Boolean {
-
-    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isBackgroundProcessingRestricted(context)) {
-      val fragmentManager = fragment.fragmentManager
-      Validate.notNull(fragmentManager)
-      val dialog = BackgroundProcessingRestrictionWarningDialog()
-      dialog.setTargetFragment(fragment, Constants.DIALOG_BACKGROUND_RESTRICTION_WARNING_CODE)
-      dialog.show(fragmentManager!!, "BACKGROUND_RESTRICTION_WARNING_DIALOG")
-      return true
-    }
-    return false
-  }
-
-  /**
-   * Shows a [BackgroundProcessingRestrictionWarningDialog] when
-   * [.isBackgroundProcessingRestricted] is true.
-   *
-   * Checks [.isBackgroundProcessingRestricted] before showing the dialog.
-   *
-   * @param activity Required to show the dialog
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun showRestrictedBackgroundProcessingWarningDialog(activity: Activity?): Boolean {
-
-    if (activity == null || activity.isFinishing) {
-      Log.w(Constants.TAG, "showRestrictedBackgroundProcessingWarningDialog: aborted, activity is null")
-      return false
-    }
-
-    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isBackgroundProcessingRestricted(activity.applicationContext)) {
-      BackgroundProcessingRestrictionWarningDialog.create(activity).show()
-      return true
-    }
-    return false
-  }
-
-  /**
-   * Shows a [ProblematicManufacturerWarningDialog] if [.isProblematicManufacturer] is true.
-   *
-   * This also checks if the user prefers not to see the dialog if he did not request guidance by himself.
-   *
-   * @param context The `Context` required to check the system settings
-   * @param fragment The `Fragment` where the dialog should be shown
-   * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
-   * template.
-   * @param force `True` if the dialog should be shown no matter of the preferences state
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
-  fun showProblematicManufacturerDialog(context: Context, fragment: Fragment, force: Boolean, recipientEmail: String): Boolean {
-
-    val preferences = PreferenceManager.getDefaultSharedPreferences(context)
-    val alreadyShown = preferences.getBoolean(Constants.PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY, false)
-    if (isProblematicManufacturer && (force || !alreadyShown)) {
-      val fragmentManager = fragment.fragmentManager
-      Validate.notNull(fragmentManager)
-      val dialog = ProblematicManufacturerWarningDialog(recipientEmail)
-      dialog.setTargetFragment(fragment, Constants.DIALOG_PROBLEMATIC_MANUFACTURER_WARNING_CODE)
-      dialog.show(fragmentManager!!, "PROBLEMATIC_MANUFACTURER_WARNING_DIALOG")
-      return true
-    }
-    return false
-  }
-
-  /**
-   * Shows a [ProblematicManufacturerWarningDialog] if [.isProblematicManufacturer] is true.
-   *
-   * This also checks if the user prefers not to see the dialog if he did not request guidance by himself.
-   *
-   * @param activity Required to show the dialog
-   * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
-   * template.
-   * @param force `True` if the dialog should be shown no matter of the preferences state
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun showProblematicManufacturerDialog(activity: Activity?, force: Boolean, recipientEmail: String): Boolean {
-
-    if (activity == null || activity.isFinishing) {
-      Log.w(Constants.TAG, "showProblematicManufacturerDialog: aborted, activity is null")
-      return false
-    }
-
-    val preferences = PreferenceManager.getDefaultSharedPreferences(activity.applicationContext)
-    val alreadyShown = preferences.getBoolean(Constants.PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY, false)
-    if (isProblematicManufacturer && (force || !alreadyShown)) {
-      ProblematicManufacturerWarningDialog.create(activity, recipientEmail).show()
-      return true
-    }
-    return false
-  }
-
-  /**
-   * Shows a [GnssDisabledWarningDialog] when [.isGpsEnabled] is true.
-   *
-   * @param context The `Context` required to check the system settings
-   * @param fragment The `Fragment` where the dialog should be shown
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
-  fun showGnssWarningDialog(context: Context, fragment: Fragment): Boolean {
-
-    if (isGnssEnabled(context)) {
-      return false
-    }
-
-    val fragmentManager = fragment.fragmentManager
-    Validate.notNull(fragmentManager)
-    val dialog = GnssDisabledWarningDialog()
-    dialog.setTargetFragment(fragment, Constants.DIALOG_GPS_DISABLED_WARNING_CODE)
-    dialog.show(fragmentManager!!, "GPS_DISABLED_WARNING_DIALOG")
-    return true
-  }
-
-  /**
-   * Shows a [GnssDisabledWarningDialog] when [.isGpsEnabled] is true.
-   *
-   * @param activity Required to show the dialog
-   * @return `True` if the dialog is shown
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun showGnssWarningDialog(activity: Activity?): Boolean {
-
-    if (activity == null || activity.isFinishing) {
-      Log.w(Constants.TAG, "showGnssWarningDialog: aborted, activity is null")
-      return false
-    }
-    val context = activity.applicationContext
-    if (isGnssEnabled(context)) {
-      return false
-    }
-
-    GnssDisabledWarningDialog.create(activity).show()
-    return true
-  }
-
-  /**
-   * Shows a [NoGuidanceNeededDialog].
-   *
-   * @param fragment The `Fragment` where the dialog should be shown
-   * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
-   * template.
-   */
-  @JvmStatic
-  @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun showNoGuidanceNeededDialog(fragment: Fragment, recipientEmail: String) {
-
-    val fragmentManager = fragment.fragmentManager
-    Validate.notNull(fragmentManager)
-    val dialog = NoGuidanceNeededDialog(recipientEmail)
-    dialog.setTargetFragment(fragment, Constants.DIALOG_NO_GUIDANCE_NEEDED_DIALOG_CODE)
-    dialog.show(fragmentManager!!, "NO_GUIDANCE_NEEDED_DIALOG")
-  }
-
-  /**
-   * Shows a [NoGuidanceNeededDialog].
-   *
-   * @param activity Required to show the dialog
-   * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
-   * template.
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun showNoGuidanceNeededDialog(activity: Activity?, recipientEmail: String) {
-
-    if (activity == null || activity.isFinishing) {
-      Log.w(Constants.TAG, "showNoGuidanceNeededDialog: aborted, activity is null")
-      return
-    }
-
-    NoGuidanceNeededDialog.create(activity, recipientEmail).show()
-  }
-
-  /**
-   * Generates an `Intent` which can be used to open an e-mail app where a new e-mail draft is opened
-   * containing a template for a feedback email.
-   *
-   * @param context The `Context` required to get the app version for the template's subject field
-   * @param extraText The title for the text area where the user can write his message. E.g. "Your message"
-   * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
-   * template.
-   * @return The intent
-   */
-  @JvmStatic
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun generateFeedbackEmailIntent(context: Context, extraText: String, recipientEmail: String): Intent {
-
-    val appVersion = getAppVersion(context)
-    val appAndDeviceInfo = prepareAppAndDeviceInformation(context, appVersion)
-    val mailSubject = (context.getString(R.string.app_name) + " " + context.getString(R.string.feedback_email_subject) + " (" + appVersion + "-"
-      + Build.VERSION.SDK_INT + ")")
-
-    val emailIntent = Intent(Intent.ACTION_SEND)
-    emailIntent.putExtra(Intent.EXTRA_EMAIL, arrayOf(recipientEmail))
-    emailIntent.putExtra(Intent.EXTRA_SUBJECT, mailSubject)
-    emailIntent.type = "plain/text"
-    emailIntent.putExtra(Intent.EXTRA_TEXT, "$appAndDeviceInfo\n---\n$extraText:\n\n\n")
-    return emailIntent
-  }
-
-  /**
-   * Load the app version as string.
-   *
-   * @param context The `Context` required to get the app version
-   * @return The app version as string
-   */
-  private fun getAppVersion(context: Context): String {
-
-    val packageManager = context.packageManager
-    return try {
-      packageManager.getPackageInfo(context.packageName, 0).versionName
-    } catch (e: PackageManager.NameNotFoundException) {
-      Log.e(Constants.TAG, "App version could not be identified: $e")
-      "N/A"
-    }
-  }
-
-  /**
-   * This function loads information about the app and device.
-   *
-   * @param context The `Context` required to get the text template
-   * @param appVersion The app version as string
-   * @return Device and app information
-   */
-  private fun prepareAppAndDeviceInformation(context: Context, appVersion: String): String {
-
-    // Replace app version, commit id and device info dynamically
-    return (context.getString(R.string.feedback_version_text) + ": " + appVersion + "\n"
-      + context.getString(R.string.feedback_device_text) + ": " + Build.MANUFACTURER + ", "
-      + Build.MODEL + " (" + Build.DEVICE + ")\n" + context.getString(R.string.feedback_android_text) + ": "
-      + Build.VERSION.RELEASE + " (API " + Build.VERSION.SDK_INT + ")")
-  }
-
-  /**
-   * Dismisses all [EnergySettingDialog]s.
-   *
-   * You can use this in your `Activity#onPause()` method to hide all dialogs from this library
-   * as the user might have changed his settings while the app is paused so you should recheck the settings
-   * in `Activity#onResume()` and only show the dialogs required then.
-   *
-   * @param fragmentManager The `FragmentManager` required to search for open dialogs.
-   */
-  @JvmStatic
-  @Deprecated("Only works with deprecated DialogFragment implementations. Should not be needed for MaterialDialogs.")
-  @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
-  fun dismissAllDialogs(fragmentManager: FragmentManager) {
-
-    val fragments = fragmentManager.fragments
-    for (fragment in fragments) {
-      if (fragment is EnergySettingDialog) {
-        fragment.dismissAllowingStateLoss()
-      }
-      val childFragmentManager = fragment.childFragmentManager
-      @Suppress("DEPRECATION") // Ok as this is called inside the method marked as deprecated
-      dismissAllDialogs(childFragmentManager)
-    }
-  }
-}
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/BackgroundProcessingRestrictionWarningDialog.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/BackgroundProcessingRestrictionWarningDialog.kt
similarity index 100%
rename from energy_settings/src/main/java/de/cyface/energy_settings/BackgroundProcessingRestrictionWarningDialog.kt
rename to energy_settings/src/main/kotlin/de/cyface/energy_settings/BackgroundProcessingRestrictionWarningDialog.kt
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/Constants.java b/energy_settings/src/main/kotlin/de/cyface/energy_settings/Constants.kt
similarity index 62%
rename from energy_settings/src/main/java/de/cyface/energy_settings/Constants.java
rename to energy_settings/src/main/kotlin/de/cyface/energy_settings/Constants.kt
index f98fbf1..2a11dd1 100644
--- a/energy_settings/src/main/java/de/cyface/energy_settings/Constants.java
+++ b/energy_settings/src/main/kotlin/de/cyface/energy_settings/Constants.kt
@@ -16,7 +16,7 @@
  * You should have received a copy of the GNU General Public License
  * along with the Cyface Energy Settings for Android. If not, see <http://www.gnu.org/licenses/>.
  */
-package de.cyface.energy_settings;
+package de.cyface.energy_settings
 
 /**
  * Holds constants required by multiple classes.
@@ -25,29 +25,28 @@
  * @version 1.0.1
  * @since 1.0.0
  */
-public final class Constants {
-
-    final static String TAG = "de.cyface.es";
-    private final static String PACKAGE = "de.cyface.energy_settings";
+@Suppress("SpellCheckingInspection")
+object Constants {
+    const val TAG = "de.cyface.es"
+    private const val PACKAGE = "de.cyface.energy_settings"
 
     // Dialog codes to identify the different dialogs
-    public final static int DIALOG_ENERGY_SAFER_WARNING_CODE = 2019071101;
-    final static int DIALOG_BACKGROUND_RESTRICTION_WARNING_CODE = 2019071102;
-    final static int DIALOG_PROBLEMATIC_MANUFACTURER_WARNING_CODE = 2019071103;
-    final static int DIALOG_GPS_DISABLED_WARNING_CODE = 2019071104;
-    final static int DIALOG_NO_GUIDANCE_NEEDED_DIALOG_CODE = 2019071105;
+    const val DIALOG_ENERGY_SAFER_WARNING_CODE = 2019071101
+    const val DIALOG_BACKGROUND_RESTRICTION_WARNING_CODE = 2019071102
+    const val DIALOG_PROBLEMATIC_MANUFACTURER_WARNING_CODE = 2019071103
+    const val DIALOG_GPS_DISABLED_WARNING_CODE = 2019071104
+    const val DIALOG_NO_GUIDANCE_NEEDED_DIALOG_CODE = 2019071105
 
     // Preference key for shared preferences
-    final static String PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY = PACKAGE + ".manufacturer_warning_shown";
+    const val PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY = "$PACKAGE.manufacturer_warning_shown"
 
     // Manufacturer names
-    final static String MANUFACTURER_HUAWEI = "huawei";
-    final static String MANUFACTURER_HONOR = "honor"; // sub brand of huawei
-    final static String MANUFACTURER_SAMSUNG = "samsung";
-    final static String MANUFACTURER_XIAOMI = "xiaomi";
-    final static String MANUFACTURER_SONY = "sony";
-
-    // The following manufacturers seem to be as restrictive as Huawei etc. (see https://dontkillmyapp.com)
+    const val MANUFACTURER_HUAWEI = "huawei"
+    const val MANUFACTURER_HONOR = "honor" // sub brand of huawei
+    const val MANUFACTURER_SAMSUNG = "samsung"
+    const val MANUFACTURER_XIAOMI = "xiaomi"
+    const val MANUFACTURER_SONY =
+        "sony" // The following manufacturers seem to be as restrictive as Huawei etc. (see https://dontkillmyapp.com)
     // but we have no negative reports yet from such devices, nor can we test them.
     // For those reasons this part is uncommented but we keep this info here as it's some work to collect this data.
     // public final static String MANUFACTURER_HTC = "htc";
@@ -58,4 +57,4 @@ public final class Constants {
     // public final static String MANUFACTURER_MEIZU = "meizu";
     // public final static String MANUFACTURER_DEWAV = "dewav";
     // public final static String MANUFACTURER_QMOBILE = "qmobile";
-}
+}
\ No newline at end of file
diff --git a/energy_settings/src/main/kotlin/de/cyface/energy_settings/CustomPreferences.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/CustomPreferences.kt
new file mode 100644
index 0000000..1a65029
--- /dev/null
+++ b/energy_settings/src/main/kotlin/de/cyface/energy_settings/CustomPreferences.kt
@@ -0,0 +1,20 @@
+package de.cyface.energy_settings
+
+import android.content.Context
+import androidx.core.content.edit
+import de.cyface.energy_settings.Constants.PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY
+import de.cyface.utils.AppPreferences
+
+class CustomPreferences(context: Context): AppPreferences(context) {
+
+    fun saveWarningShown(warningShown: Boolean) {
+        preferences.edit {
+            putBoolean(PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY, warningShown)
+            apply()
+        }
+    }
+
+    fun getWarningShown(): Boolean {
+        return preferences.getBoolean(PREFERENCES_MANUFACTURER_WARNING_SHOWN_KEY, false)
+    }
+}
\ No newline at end of file
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/EnergySaferWarningDialog.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/EnergySaferWarningDialog.kt
similarity index 100%
rename from energy_settings/src/main/java/de/cyface/energy_settings/EnergySaferWarningDialog.kt
rename to energy_settings/src/main/kotlin/de/cyface/energy_settings/EnergySaferWarningDialog.kt
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/EnergySettingDialog.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/EnergySettingDialog.kt
similarity index 100%
rename from energy_settings/src/main/java/de/cyface/energy_settings/EnergySettingDialog.kt
rename to energy_settings/src/main/kotlin/de/cyface/energy_settings/EnergySettingDialog.kt
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/GnssDisabledWarningDialog.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/GnssDisabledWarningDialog.kt
similarity index 100%
rename from energy_settings/src/main/java/de/cyface/energy_settings/GnssDisabledWarningDialog.kt
rename to energy_settings/src/main/kotlin/de/cyface/energy_settings/GnssDisabledWarningDialog.kt
diff --git a/energy_settings/src/main/java/de/cyface/energy_settings/NoGuidanceNeededDialog.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/NoGuidanceNeededDialog.kt
similarity index 100%
rename from energy_settings/src/main/java/de/cyface/energy_settings/NoGuidanceNeededDialog.kt
rename to energy_settings/src/main/kotlin/de/cyface/energy_settings/NoGuidanceNeededDialog.kt
diff --git a/energy_settings/src/main/kotlin/de/cyface/energy_settings/ProblematicManufacturerWarningDialog.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/ProblematicManufacturerWarningDialog.kt
new file mode 100644
index 0000000..e1301a6
--- /dev/null
+++ b/energy_settings/src/main/kotlin/de/cyface/energy_settings/ProblematicManufacturerWarningDialog.kt
@@ -0,0 +1,507 @@
+/*
+ * Copyright 2019-2023 Cyface GmbH
+ *
+ * This file is part of the Cyface Energy Settings for Android.
+ *
+ * The Cyface Energy Settings for Android is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * The Cyface Energy Settings for Android is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with the Cyface Energy Settings for Android. If not, see <http://www.gnu.org/licenses/>.
+ */
+package de.cyface.energy_settings
+
+import android.app.Activity
+import android.app.AlertDialog
+import android.app.Dialog
+import android.content.ComponentName
+import android.content.Context
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.os.Build
+import android.os.Bundle
+import android.util.Log
+import com.afollestad.materialdialogs.MaterialDialog
+import de.cyface.energy_settings.Constants.TAG
+import de.cyface.energy_settings.GnssDisabledWarningDialog.Companion.create
+import de.cyface.energy_settings.ProblematicManufacturerWarningDialog.Companion.create
+import java.util.Locale
+
+/**
+ * Dialog to show a warning when a phone manufacturer is identified which allows to prevent background tracking
+ * by manufacturer-specific settings.
+ *
+ * This dialog is customized by searching for a match in a known list of manufacturer-specific energy settings pages.
+ * If a match is found the required steps to adjust the settings are shown and the setting page is accessible via a
+ * dialog button. Else, a generic text is shown in the dialog to help the user finding the energy settings by itself.
+ *
+ * This dialog also contains a button which allows the user to disable the auto-popup of this dialog.
+ * This preference is not respected when the user requests guidance explicitly.
+ *
+ * Two implementation are available:
+ *
+ * 1. As `DialogFragment`. Use the constructor and use the dialog. Calls [onCreateDialog] internally.
+ * 2. As [MaterialDialog]. Use the static [create] method which returns the dialog.
+ *
+ * @author Armin Schnabel
+ * @version 2.1.0
+ * @since 1.0.0
+ *
+ * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated template.
+ */
+internal class ProblematicManufacturerWarningDialog(private val recipientEmail: String) :
+    EnergySettingDialog() {
+
+    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
+
+        // Generate dialog
+        val builder = AlertDialog.Builder(activity)
+        builder.setTitle(titleRes)
+
+        // Allow the user to express its preference to disable auto-popup of this dialog
+        builder.setNegativeButton(negativeButtonRes) { _, _ ->
+            onNegativeButtonCall(context)
+        }
+
+        // Show Sony STAMINA specific dialog (no manufacturer specific intent name known yet)
+        val messageRes = if (isSony()) sonyStaminaMessageRes else genericMessageRes
+
+        // Context-less scenario
+        val context = context
+        if (context == null) {
+            Log.w(TAG, "No ProblematicManufacturerWarningDialog shown, context is null.")
+            builder.setMessage(messageRes)
+            return builder.create()
+        }
+
+        // If a device specific settings page is found, add a button to open it directly
+        val deviceSpecificIntent = getDeviceSpecificIntent(context)
+        if (deviceSpecificIntent != null) {
+
+            // [STAD-492] Since 2021 Huawei started to deny opening the Huawei "App Launch" setting via intent.
+            val unreachableSetting =
+                deviceSpecificIntent.key.component!!.className.equals("com.huawei.systemmanager.startupmgr.ui.StartupNormalAppListActivity")
+            return if (unreachableSetting) {
+                builder.setMessage(deviceSpecificIntent.value) // Use the message for the identified intent
+                builder.setPositiveButton(feedbackButtonRes) { _, _ ->
+                    startActivity(
+                        Intent.createChooser(
+                            intent(context, recipientEmail),
+                            getString(chooseEmailAppRes)
+                        )
+                    )
+                }
+                builder.create()
+            } else {
+                val settingsIntent = deviceSpecificIntent.key
+                builder.setMessage(deviceSpecificIntent.value)
+                builder.setPositiveButton(openSettingsButtonRes) { _, _ ->
+                    startActivity(
+                        settingsIntent
+                    )
+                }
+                builder.create()
+            }
+        } else {
+
+            // Generate a feedback button
+            builder.setPositiveButton(feedbackButtonRes) { _, _ ->
+                startActivity(
+                    Intent.createChooser(
+                        intent(context, recipientEmail),
+                        getString(chooseEmailAppRes)
+                    )
+                )
+            }
+
+            builder.setMessage(messageRes)
+            return builder.create()
+        }
+    }
+
+    companion object {
+        /**
+         * The resource pointing to the text used as title.
+         */
+        private val titleRes = R.string.dialog_problematic_manufacturer_warning_title
+
+        /**
+         * The resource pointing to the text of the generic dialog which is shown when no manufacturer-specific
+         * energy setting page is found
+         */
+        private var genericMessageRes = R.string.dialog_manufacturer_warning_generic
+
+        /**
+         * The resource pointing to the text of the dialog which is shown when no manufacturer-specific
+         * energy setting page is found but a sony device is detected
+         */
+        private val sonyStaminaMessageRes = R.string.dialog_manufacturer_warning_sony_stamina
+
+        /**
+         * The resource pointing to the text used as positive button which opens the settings.
+         */
+        private val openSettingsButtonRes = R.string.dialog_button_open_settings
+
+        /**
+         * The resource pointing to the text used as positive button which opens a feedback email template.
+         */
+        private val feedbackButtonRes = R.string.dialog_button_help
+
+        /**
+         * The resource pointing to the text used as negative button which stores the "don't show again" preference.
+         */
+        private val negativeButtonRes = R.string.dialog_button_do_not_show_again
+
+        private fun isSony(): Boolean {
+            return Build.MANUFACTURER.lowercase(Locale.ROOT) == Constants.MANUFACTURER_SONY
+        }
+
+        /**
+         * Saves the user's preference to disable auto-popup of this dialog
+         */
+        private fun onNegativeButtonCall(context: Context?) {
+            CustomPreferences(context!!).saveWarningShown(true)
+        }
+
+        /**
+         * Alternative, `FragmentManager`-less implementation.
+         *
+         * @param activity Required to show the dialog
+         */
+        fun create(activity: Activity, recipientEmail: String): MaterialDialog {
+
+            // Generate dialog
+            val dialog = MaterialDialog(activity, DIALOG_BEHAVIOUR)
+            dialog.title(titleRes, null)
+
+            // Allow the user to express its preference to disable auto-popup of this dialog
+            dialog.negativeButton(negativeButtonRes) {
+                onNegativeButtonCall(activity.applicationContext)
+            }
+
+            // Show Sony STAMINA specific dialog (no manufacturer specific intent name known yet)
+            val messageRes = if (isSony()) sonyStaminaMessageRes else genericMessageRes
+
+            // Context-less scenario
+            val context = activity.applicationContext
+            if (context == null) {
+                Log.w(TAG, "No ProblematicManufacturerWarningDialog shown, context is null.")
+                dialog.message(messageRes)
+                return dialog
+            }
+
+            // If a device specific settings page is found, add a button to open it directly
+            val deviceSpecificIntent = getDeviceSpecificIntent(context)
+            if (deviceSpecificIntent != null) {
+
+                // [STAD-492] Since 2021 Huawei started to deny opening the Huawei "App Launch" setting via intent.
+                val unreachable =
+                    deviceSpecificIntent.key.component!!.className.equals("com.huawei.systemmanager.startupmgr.ui.StartupNormalAppListActivity")
+                return if (unreachable) {
+                    dialog.positiveButton(feedbackButtonRes) {
+                        activity.startActivity(
+                            Intent.createChooser(
+                                intent(context, recipientEmail),
+                                context.getString(chooseEmailAppRes)
+                            )
+                        )
+                    }
+                    dialog.message(deviceSpecificIntent.value) // Use the message for the identified intent
+                    dialog
+                } else {
+                    val settingsIntent = deviceSpecificIntent.key
+                    dialog.positiveButton(openSettingsButtonRes) {
+                        activity.startActivity(
+                            settingsIntent
+                        )
+                    }
+                    dialog.message(deviceSpecificIntent.value)
+                    dialog
+                }
+            } else {
+
+                // Generate a feedback button
+                dialog.positiveButton(feedbackButtonRes) {
+                    activity.startActivity(
+                        Intent.createChooser(
+                            intent(context, recipientEmail),
+                            context.getString(chooseEmailAppRes)
+                        )
+                    )
+                }
+
+                dialog.message(messageRes)
+                return dialog
+            }
+        }
+
+        /**
+         * Searches for a match of a list of known device-specific energy setting pages.
+         *
+         * @param context The [Context] to check if the intent is resolvable on this device
+         * @return The intent to open the settings page and the resource id of the message string which describes what to do
+         * on the settings page. Returns `Null` if no intent was resolved. Always returns the first match,
+         * which means the intent which was added in a later Android version if there are multiple matches.
+         */
+        private fun getDeviceSpecificIntent(context: Context): Map.Entry<Intent, Int>? {
+            // (!) This needs to be an ordered map or else StartupAppControlActivity might be returned in favor
+            // of StartupNormalAppListActivity if both exist which leads to an error [MOV-989]
+            val intentMap: MutableMap<Intent, Int> = LinkedHashMap()
+
+            /*
+             * Huawei/Honor
+             * - EMUI OS (https://de.wikipedia.org/wiki/EMUI#Versionen)
+             *******************************************************************************************/
+
+            // "App-Start", e.g. EMUI 9, 10
+
+            // [STAD-492] Since 2021 Huawei started to deny opening the Huawei "App Launch" setting via intent.
+            // A SecurityException is thrown. I.e. the user now has to navigate on it's own to the settings.
+            // On our test devices this cannot be reproduced but we see this frequently now in the Play Console.
+            // But as we only see the crashes in Android 10, we leave `< Build.VERSION_CODES.Q` as it is.
+            // We need to leave both intents here, so that the correct text is shown in the dialog.
+            // We only disable the settings-button where `getDeviceSpecificIntent()` is called.
+
+            // [MOV-989] On EMUI 10.0.0 (e.g. our P smart 2019) it finds both:
+            // 1. StartupNormalAppListActivity (which works on new EMUI versions)
+            // 2. StartupAppControlActivity (which crashes on new EMUI even with USE_COMPONENT permission)
+            // This is why we need to keep the intents here in an ordered map with (1) earlier in the map
+            // This way always (1) is returned before (2)
+
+            // P20, EMUI 9, Android 9, 2019 - comment in https://stackoverflow.com/a/48641229/5815054
+            // when adding the permissions above does not work with the intent above
+            intentMap[Intent().setComponent(
+                ComponentName(
+                    "com.huawei.systemmanager",
+                    "com.huawei.systemmanager.startupmgr.ui.StartupNormalAppListActivity"
+                )
+            )] = R.string.dialog_manufacturer_warning_huawei_app_launch
+
+            // P20, EMUI 9, Android 9, 2018 - comment in https://stackoverflow.com/a/35220476/5815054
+            // [STAD-280] This check should not be necessary as `StartupNormalAppListActivity` should
+            // always be prioritised by the current code if both are found. However, on some Android 10
+            // devices it seems like this activity is still called. Thus, we completely disable it on Q+.
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
+                intentMap[Intent().setComponent(
+                    ComponentName(
+                        "com.huawei.systemmanager",
+                        "com.huawei.systemmanager.appcontrol.activity.StartupAppControlActivity"
+                    )
+                )] = R.string.dialog_manufacturer_warning_huawei_app_launch
+            }
+
+            // "Protected Apps", EMUI <5, Android <7
+            intentMap[Intent().setComponent(
+                ComponentName(
+                    "com.huawei.systemmanager",
+                    "com.huawei.systemmanager.optimize.process.ProtectActivity"
+                )
+            )] = R.string.dialog_manufacturer_warning_huawei_protected_app
+
+            /*
+             * Samsung
+             * - One UI (https://de.wikipedia.org/wiki/One_UI)
+             * - TouchWiz (https://en.wikipedia.org/wiki/TouchWiz)
+             *******************************************************************************************/
+
+            // Android 7+, "Unmonitored Apps"
+            // - http://sleep.urbandroid.org/documentation/faq/alarms-sleep-tracking-dont-work/#sleeping-apps
+            // - Unable to test if this is necessary as we don't have a Samsung Android 7 device
+            intentMap[Intent().setComponent(
+                ComponentName(
+                    "com.samsung.android.lool",
+                    "com.samsung.android.sm.ui.battery.BatteryActivity"
+                )
+            )] = R.string.dialog_manufacturer_warning_samsung_device_care
+
+            // Android 5-6 - https://code.briarproject.org/briar/briar/issues/1100
+            // - tested: settings found and opened on Android 6.0.1 (office phone: S5 neo)
+            // - by default (our phone) this was off but people might have enabled both general and app-specific option
+            intentMap[Intent().setComponent(
+                ComponentName(
+                    "com.samsung.android.sm",
+                    "com.samsung.android.sm.ui.battery.BatteryActivity"
+                )
+            )] = R.string.dialog_manufacturer_warning_samsung_smart_manager
+
+            /*
+             * Xiaomi
+             * - MIUI (https://en.wikipedia.org/wiki/MIUI#Version_history)
+             *******************************************************************************************/
+
+            // Tested on Redmi Note 5 (Android 8.1, MIUI 10)
+            intentMap[Intent().setComponent(
+                ComponentName(
+                    "com.miui.securitycenter",
+                    "com.miui.powercenter.PowerSettings"
+                )
+            )] = R.string.dialog_manufacturer_warning_xiaomi_power_settings
+            intentMap[Intent().setComponent(
+                ComponentName(
+                    "com.miui.securitycenter",
+                    "com.miui.permcenter.autostart.AutoStartManagementActivity"
+                )
+            )] = R.string.dialog_manufacturer_warning_xiaomi_auto_start
+
+            // from https://github.com/dirkam/backgroundable-android
+            // Unsure if this is the correct dialog
+            intentMap[Intent("miui.intent.action.POWER_HIDE_MODE_APP_LIST").addCategory(Intent.CATEGORY_DEFAULT)] =
+                R.string.dialog_manufacturer_warning_xiaomi_power_settings
+
+            // Unsure if this is the correct dialog
+            intentMap[Intent("miui.intent.action.OP_AUTO_START").addCategory(Intent.CATEGORY_DEFAULT)] =
+                R.string.dialog_manufacturer_warning_xiaomi_auto_start
+
+            /*
+             * Other manufacturers
+             * - The following manufacturers seem to be as restrictive as Huawei etc. (see https://dontkillmyapp.com)
+             * - but we have no negative reports yet from such devices, nor can we test them.
+             * - For those reasons this part is uncommented but we keep this info here as it's some work to collect this
+             * data.
+             *******************************************************************************************/
+
+            /*
+             * HTC
+             * - Boost+ App https://www.htc.com/de/support/htc-one-a9s/howto/830580.html
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.htc.pitroad",
+             * "com.htc.pitroad.landingpage.activity.LandingPageActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *******************************************************************************************/
+
+            /*
+             * Oppo
+             *
+             * Might require the following permissions:
+             * From comment in https://stackoverflow.com/a/48641229/5815054 - required for
+             * com.coloros.safecenter/.startupapp.StartupAppListActivity
+             * <uses-permission android:name="oppo.permission.OPPO_COMPONENT_SAFE"/>
+             * From https://stackoverflow.com/a/51726040/5815054
+             * <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"/>
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.safecenter",
+             * "com.coloros.safecenter.permission.startup.StartupAppListActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * // From https://stackoverflow.com/a/51726040/5815054 and https://github.com/dirkam/backgroundable-android
+             * // Android >= 7 (ColorOS >= 3)
+             * if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.safecenter",
+             * "com.coloros.safecenter.startupapp.StartupAppListActivity")).setAction(Settings.
+             * / * VIOLATION WARNING: ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS * /
+             * ACTION_IGNORE_BATTERY_OPTIMIZATION_SETTINGS)
+             * .setData(Uri.parse("package:" + context.getPackageName())),
+             * R.string.dialog_manufacturer_warning_generic);
+             * }
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.oppo.safe",
+             * "com.oppo.safe.permission.startup.StartupAppListActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * // From https://stackoverflow.com/a/51726040/5815054
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.oppoguardelf",
+             * "com.coloros.powermanager.fuelgaue.PowerUsageModelActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.oppoguardelf",
+             * "com.coloros.powermanager.fuelgaue.PowerSaverModeActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.coloros.oppoguardelf",
+             * "com.coloros.powermanager.fuelgaue.PowerConsumptionActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            /*
+             * Asus
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.asus.mobilemanager",
+             * "com.asus.mobilemanager.MainActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * // From https://stackoverflow.com/a/51726040/5815054
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.asus.mobilemanager",
+             * "com.asus.mobilemanager.entry.FunctionActivity"))
+             * // From https://stackoverflow.com/a/49110392/5815054
+             * .setData(Uri.parse("mobilemanager://function/entry/AutoStart")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.asus.mobilemanager",
+             * "com.asus.mobilemanager.autostart.AutoStartActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            /*
+             * Letv
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.letv.android.letvsafe",
+             * "com.letv.android.letvsafe.AutobootManageActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            /*
+             * Meizu
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.meizu.safe",
+             * "com.meizu.safe.security.SHOW_APPSEC"))
+             * .addCategory(Intent.CATEGORY_DEFAULT).putExtra("packageName", BuildConfig.APPLICATION_ID),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            /*
+             * Vivo
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.iqoo.secure",
+             * "com.iqoo.secure.ui.phoneoptimize.AddWhiteListActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.vivo.permissionmanager",
+             * "com.vivo.permissionmanager.activity.BgStartUpManagerActivity")),
+             * R.string.dialog_manufacturer_warning_generic);
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.iqoo.secure",
+             * "com.iqoo.secure.ui.phoneoptimize.BgStartUpManager")),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            /*
+             * Dewav
+             * - https://stackoverflow.com/a/49110392/5815054
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.dewav.dwappmanager",
+             * "com.dewav.dwappmanager.memory.SmartClearupWhiteList")),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            /*
+             * Qmobile
+             * - from comment in https://stackoverflow.com/a/49110392/5815054
+             *
+             * intentMap.put(new Intent().setComponent(new ComponentName("com.dewav.dwappmanager",
+             * "com.dewav.dwappmanager.memory.SmartClearupWhiteList")),
+             * R.string.dialog_manufacturer_warning_generic);
+             */
+
+            // Search for a match in the list of known energy settings pages
+            // Return the first match. If not this leads to [MOV-989], see note above.
+            for (entry in intentMap.entries) {
+                if (context.packageManager.resolveActivity(
+                        entry.key,
+                        PackageManager.MATCH_DEFAULT_ONLY
+                    ) != null
+                ) {
+                    return entry
+                }
+            }
+
+            return null
+        }
+    }
+}
diff --git a/energy_settings/src/main/kotlin/de/cyface/energy_settings/TrackingSettings.kt b/energy_settings/src/main/kotlin/de/cyface/energy_settings/TrackingSettings.kt
new file mode 100644
index 0000000..e19b892
--- /dev/null
+++ b/energy_settings/src/main/kotlin/de/cyface/energy_settings/TrackingSettings.kt
@@ -0,0 +1,536 @@
+/*
+ * Copyright 2019-2023 Cyface GmbH
+ *
+ * This file is part of the Cyface Energy Settings for Android.
+ *
+ * The Cyface Energy Settings for Android is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * The Cyface Energy Settings for Android is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with the Cyface Energy Settings for Android. If not, see <http://www.gnu.org/licenses/>.
+ */
+package de.cyface.energy_settings
+
+import android.app.Activity
+import android.app.ActivityManager
+import android.content.Context
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.location.LocationManager
+import android.os.Build
+import android.os.PowerManager
+import android.util.Log
+import androidx.annotation.RequiresApi
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentManager
+import de.cyface.utils.Validate
+import java.util.Locale
+
+/**
+ * Holds the API for this energy setting library.
+ *
+ * Offers checks and dialogs for energy settings required for background tracking.
+ *
+ * @author Armin Schnabel
+ * @version 2.0.3
+ * @since 1.0.0
+ */
+object TrackingSettings {
+
+    /**
+     * Checks whether the energy safer mode is active *at this moment*.
+     *
+     * If this mode is active the GPS location service is disabled on most devices.
+     *
+     * API 28+
+     * - due to Android documentation GPS is only disabled starting with API 28 when the display is off
+     * - manufacturers can change this. On a Pixel 2 XL e.g. GPS is offline. On most other devices, too.
+     * - we explicitly check if this is the case on the device and only return true if GPS gets disabled
+     *
+     * API < 28
+     * - Some manufacturers implemented an own energy saving mode (e.g. on Honor 8, Android 7) which also kills GPS
+     * when this mode is active and the display disabled. Thus, we don't also don't allow energy safer mode on lower
+     * APIs.
+     *
+     * @param context The `Context` required to check the system settings
+     * @return `True` if an energy safer mode is currently active which very likely disables the GPS service
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun isEnergySaferActive(context: Context): Boolean {
+
+        val powerManager = context.getSystemService(Context.POWER_SERVICE) as PowerManager
+        val isInPowerSavingMode = powerManager.isPowerSaveMode
+
+        // On newer APIs we can check if the power safer mode actually kills location tracking in background
+        return if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) {
+            isInPowerSavingMode
+        } else isInPowerSavingMode
+                && powerManager.locationPowerSaveMode != PowerManager.LOCATION_MODE_FOREGROUND_ONLY
+                && powerManager.locationPowerSaveMode != PowerManager.LOCATION_MODE_NO_CHANGE
+    }
+
+    /**
+     * Checks whether background processing is restricted by the settings.
+     *
+     * If this mode is enabled, the background processing is paused when the app is in background or the display is off.
+     *
+     * This was tested on a Pixel 2 XL device. Here this setting is disabled by default.
+     * On other manufacturers, e.g. on Xiaomi's MIUI this setting is enabled by default.
+     *
+     * @param context The `Context` required to check the system settings
+     * @return `True` if the processing is restricted
+     */
+    @JvmStatic
+    @RequiresApi(api = Build.VERSION_CODES.P)
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun isBackgroundProcessingRestricted(context: Context): Boolean {
+
+        val activityManager = context.getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
+        return (activityManager.isBackgroundRestricted)
+    }
+
+    /**
+     * Checks whether a manufacturer was identified which implements manufacturer-specific energy settings known to
+     * prevent background tracking when set up wrong or even with the default settings.
+     *
+     * @return `True` if such a manufacturer is identified
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate", "SpellCheckingInspection") // Used by implementing app
+    val isProblematicManufacturer: Boolean
+        get() {
+
+            return when (Build.MANUFACTURER.lowercase(Locale.ROOT)) {
+                Constants.MANUFACTURER_HUAWEI, Constants.MANUFACTURER_HONOR, Constants.MANUFACTURER_SAMSUNG,
+                Constants.MANUFACTURER_XIAOMI, Constants.MANUFACTURER_SONY -> true
+                /* Sony STAMINA
+                 * - On Android 8 we may be able to check if STAMINA is disabled completely according to:
+                 * https://stackoverflow.com/a/50740898/5815054/, https://dontkillmyapp.com/sony
+                 * Settings.Secure.getInt(context.getContentResolver(), "somc.stamina_mode", 0) > 0;
+                 * - However, as this does not work on Android 6 we just show the warning to all SONY phones
+                 */
+                /*
+                 * Other manufacturers
+                 * - The following manufacturers seem to be as restrictive as Huawei etc. (see
+                 * https://dontkillmyapp.com)
+                 * - but we have no negative reports yet from such devices, nor can we test them.
+                 * - For those reasons this part is uncommented but we keep this info here as it's some work to collect
+                 * this data.
+                 *
+                 * case MANUFACTURER_HTC:
+                 * case MANUFACTURER_OPPO:
+                 * case MANUFACTURER_ASUS:
+                 * case MANUFACTURER_LETV:
+                 * case MANUFACTURER_VIVO:
+                 * case MANUFACTURER_MEIZU:
+                 * case MANUFACTURER_DEWAV:
+                 * case MANUFACTURER_QMOBILE:
+                 */
+                else -> false
+            }
+        }
+
+    /**
+     * Checks whether GPS is enabled in the settings.
+     *
+     * @param context The `Context` required to check the system settings
+     * @return `True` if GPS is enabled
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun isGnssEnabled(context: Context): Boolean {
+
+        val manager = context.getSystemService(Context.LOCATION_SERVICE) as LocationManager
+        return manager.isProviderEnabled(LocationManager.GPS_PROVIDER)
+    }
+
+    /*
+     * Battery Optimization setting
+     *
+     * - Tests showed that this option should not be needed. (It also may sound scary to the user.)
+     * - Android settings explain that this setting is only needed if the was not Doze-optimized.
+     * - Our app should be Doze-optimized - which our tests indicated, too.
+     *
+     * else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M
+     * && powerManager != null && !powerManager.isIgnoringBatteryOptimizations(packageName)) {
+     *
+     * There are two native dialogs which can be popped up:
+     *
+     * 1) Request direct white-listing
+     * - this is not allowed in all cases and can end up in a denied play store release
+     * - this would required the following permissions:
+     * <uses-permission
+     * android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"/>
+     *
+     * 2) Open the settings page where the user hat to white-list the app himself
+     * final Intent intent = new Intent();
+     * intent.setAction(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS);
+     * intent.setData(Uri.parse("package:" + packageName));
+     * fragmentRoot.getContext().startActivity(intent);
+     * }
+     */
+
+    /**
+     * Shows a [EnergySaferWarningDialog] when [.isEnergySaferActive] is true.
+     *
+     * Checks [.isEnergySaferActive] before showing the dialog.
+     *
+     * @param context The `Context` required to check the system settings
+     * @param fragment The `Fragment` where the dialog should be shown
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
+    fun showEnergySaferWarningDialog(context: Context, fragment: Fragment): Boolean {
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isEnergySaferActive(context)) {
+            val fragmentManager = fragment.fragmentManager
+            Validate.notNull(fragmentManager)
+            val dialog = EnergySaferWarningDialog()
+            dialog.setTargetFragment(fragment, Constants.DIALOG_ENERGY_SAFER_WARNING_CODE)
+            dialog.show(fragmentManager!!, "ENERGY_SAFER_WARNING_DIALOG")
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Shows a [EnergySaferWarningDialog] when [.isEnergySaferActive] is true.
+     *
+     * Checks [.isEnergySaferActive] before showing the dialog.
+     *
+     * @param activity Required to show the dialog
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun showEnergySaferWarningDialog(activity: Activity?): Boolean {
+
+        if (activity == null || activity.isFinishing) {
+            Log.w(Constants.TAG, "showEnergySaferWarningDialog: aborted, activity is null")
+            return false
+        }
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isEnergySaferActive(activity.applicationContext)) {
+            EnergySaferWarningDialog.create(activity).show()
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Shows a [BackgroundProcessingRestrictionWarningDialog] when
+     * [.isBackgroundProcessingRestricted] is true.
+     *
+     * Checks [.isBackgroundProcessingRestricted] before showing the dialog.
+     *
+     * @param context The `Context` required to check the system settings
+     * @param fragment The `Fragment` where the dialog should be shown
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
+    fun showRestrictedBackgroundProcessingWarningDialog(
+        context: Context,
+        fragment: Fragment
+    ): Boolean {
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isBackgroundProcessingRestricted(
+                context
+            )
+        ) {
+            val fragmentManager = fragment.fragmentManager
+            Validate.notNull(fragmentManager)
+            val dialog = BackgroundProcessingRestrictionWarningDialog()
+            dialog.setTargetFragment(fragment, Constants.DIALOG_BACKGROUND_RESTRICTION_WARNING_CODE)
+            dialog.show(fragmentManager!!, "BACKGROUND_RESTRICTION_WARNING_DIALOG")
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Shows a [BackgroundProcessingRestrictionWarningDialog] when
+     * [.isBackgroundProcessingRestricted] is true.
+     *
+     * Checks [.isBackgroundProcessingRestricted] before showing the dialog.
+     *
+     * @param activity Required to show the dialog
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun showRestrictedBackgroundProcessingWarningDialog(activity: Activity?): Boolean {
+
+        if (activity == null || activity.isFinishing) {
+            Log.w(
+                Constants.TAG,
+                "showRestrictedBackgroundProcessingWarningDialog: aborted, activity is null"
+            )
+            return false
+        }
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P && isBackgroundProcessingRestricted(
+                activity.applicationContext
+            )
+        ) {
+            BackgroundProcessingRestrictionWarningDialog.create(activity).show()
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Shows a [ProblematicManufacturerWarningDialog] if [.isProblematicManufacturer] is true.
+     *
+     * This also checks if the user prefers not to see the dialog if he did not request guidance by himself.
+     *
+     * @param context The `Context` required to check the system settings
+     * @param fragment The `Fragment` where the dialog should be shown
+     * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
+     * template.
+     * @param force `True` if the dialog should be shown no matter of the preferences state
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
+    fun showProblematicManufacturerDialog(
+        context: Context,
+        fragment: Fragment,
+        force: Boolean,
+        recipientEmail: String
+    ): Boolean {
+
+        val preferences = CustomPreferences(context)
+        if (isProblematicManufacturer && (force || !preferences.getWarningShown())) {
+            val fragmentManager = fragment.fragmentManager
+            Validate.notNull(fragmentManager)
+            val dialog = ProblematicManufacturerWarningDialog(recipientEmail)
+            dialog.setTargetFragment(
+                fragment,
+                Constants.DIALOG_PROBLEMATIC_MANUFACTURER_WARNING_CODE
+            )
+            dialog.show(fragmentManager!!, "PROBLEMATIC_MANUFACTURER_WARNING_DIALOG")
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Shows a [ProblematicManufacturerWarningDialog] if [.isProblematicManufacturer] is true.
+     *
+     * This also checks if the user prefers not to see the dialog if he did not request guidance by himself.
+     *
+     * @param activity Required to show the dialog
+     * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
+     * template.
+     * @param force `True` if the dialog should be shown no matter of the preferences state
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun showProblematicManufacturerDialog(
+        activity: Activity?,
+        force: Boolean,
+        recipientEmail: String
+    ): Boolean {
+
+        if (activity == null || activity.isFinishing) {
+            Log.w(Constants.TAG, "showProblematicManufacturerDialog: aborted, activity is null")
+            return false
+        }
+
+        val preferences = CustomPreferences(activity.applicationContext)
+        if (isProblematicManufacturer && (force || !preferences.getWarningShown())) {
+            ProblematicManufacturerWarningDialog.create(activity, recipientEmail).show()
+            return true
+        }
+        return false
+    }
+
+    /**
+     * Shows a [GnssDisabledWarningDialog] when [.isGpsEnabled] is true.
+     *
+     * @param context The `Context` required to check the system settings
+     * @param fragment The `Fragment` where the dialog should be shown
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
+    fun showGnssWarningDialog(context: Context, fragment: Fragment): Boolean {
+
+        if (isGnssEnabled(context)) {
+            return false
+        }
+
+        val fragmentManager = fragment.fragmentManager
+        Validate.notNull(fragmentManager)
+        val dialog = GnssDisabledWarningDialog()
+        dialog.setTargetFragment(fragment, Constants.DIALOG_GPS_DISABLED_WARNING_CODE)
+        dialog.show(fragmentManager!!, "GPS_DISABLED_WARNING_DIALOG")
+        return true
+    }
+
+    /**
+     * Shows a [GnssDisabledWarningDialog] when [.isGpsEnabled] is true.
+     *
+     * @param activity Required to show the dialog
+     * @return `True` if the dialog is shown
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun showGnssWarningDialog(activity: Activity?): Boolean {
+
+        if (activity == null || activity.isFinishing) {
+            Log.w(Constants.TAG, "showGnssWarningDialog: aborted, activity is null")
+            return false
+        }
+        val context = activity.applicationContext
+        if (isGnssEnabled(context)) {
+            return false
+        }
+
+        GnssDisabledWarningDialog.create(activity).show()
+        return true
+    }
+
+    /**
+     * Shows a [NoGuidanceNeededDialog].
+     *
+     * @param fragment The `Fragment` where the dialog should be shown
+     * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
+     * template.
+     */
+    @JvmStatic
+    @Deprecated("Alternative implementation recommended as this one is currently not being tested.")
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun showNoGuidanceNeededDialog(fragment: Fragment, recipientEmail: String) {
+
+        val fragmentManager = fragment.fragmentManager
+        Validate.notNull(fragmentManager)
+        val dialog = NoGuidanceNeededDialog(recipientEmail)
+        dialog.setTargetFragment(fragment, Constants.DIALOG_NO_GUIDANCE_NEEDED_DIALOG_CODE)
+        dialog.show(fragmentManager!!, "NO_GUIDANCE_NEEDED_DIALOG")
+    }
+
+    /**
+     * Shows a [NoGuidanceNeededDialog].
+     *
+     * @param activity Required to show the dialog
+     * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
+     * template.
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun showNoGuidanceNeededDialog(activity: Activity?, recipientEmail: String) {
+
+        if (activity == null || activity.isFinishing) {
+            Log.w(Constants.TAG, "showNoGuidanceNeededDialog: aborted, activity is null")
+            return
+        }
+
+        NoGuidanceNeededDialog.create(activity, recipientEmail).show()
+    }
+
+    /**
+     * Generates an `Intent` which can be used to open an e-mail app where a new e-mail draft is opened
+     * containing a template for a feedback email.
+     *
+     * @param context The `Context` required to get the app version for the template's subject field
+     * @param extraText The title for the text area where the user can write his message. E.g. "Your message"
+     * @param recipientEmail The e-mail address to which the feedback email should be addressed to in the generated
+     * template.
+     * @return The intent
+     */
+    @JvmStatic
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun generateFeedbackEmailIntent(
+        context: Context,
+        extraText: String,
+        recipientEmail: String
+    ): Intent {
+
+        val appVersion = getAppVersion(context)
+        val appAndDeviceInfo = prepareAppAndDeviceInformation(context, appVersion)
+        val mailSubject =
+            (context.getString(R.string.app_name) + " " + context.getString(R.string.feedback_email_subject) + " (" + appVersion + "-"
+                    + Build.VERSION.SDK_INT + ")")
+
+        val emailIntent = Intent(Intent.ACTION_SEND)
+        emailIntent.putExtra(Intent.EXTRA_EMAIL, arrayOf(recipientEmail))
+        emailIntent.putExtra(Intent.EXTRA_SUBJECT, mailSubject)
+        emailIntent.type = "plain/text"
+        emailIntent.putExtra(Intent.EXTRA_TEXT, "$appAndDeviceInfo\n---\n$extraText:\n\n\n")
+        return emailIntent
+    }
+
+    /**
+     * Load the app version as string.
+     *
+     * @param context The `Context` required to get the app version
+     * @return The app version as string
+     */
+    private fun getAppVersion(context: Context): String {
+
+        val packageManager = context.packageManager
+        return try {
+            packageManager.getPackageInfo(context.packageName, 0).versionName
+        } catch (e: PackageManager.NameNotFoundException) {
+            Log.e(Constants.TAG, "App version could not be identified: $e")
+            "N/A"
+        }
+    }
+
+    /**
+     * This function loads information about the app and device.
+     *
+     * @param context The `Context` required to get the text template
+     * @param appVersion The app version as string
+     * @return Device and app information
+     */
+    private fun prepareAppAndDeviceInformation(context: Context, appVersion: String): String {
+
+        // Replace app version, commit id and device info dynamically
+        return (context.getString(R.string.feedback_version_text) + ": " + appVersion + "\n"
+                + context.getString(R.string.feedback_device_text) + ": " + Build.MANUFACTURER + ", "
+                + Build.MODEL + " (" + Build.DEVICE + ")\n" + context.getString(R.string.feedback_android_text) + ": "
+                + Build.VERSION.RELEASE + " (API " + Build.VERSION.SDK_INT + ")")
+    }
+
+    /**
+     * Dismisses all [EnergySettingDialog]s.
+     *
+     * You can use this in your `Activity#onPause()` method to hide all dialogs from this library
+     * as the user might have changed his settings while the app is paused so you should recheck the settings
+     * in `Activity#onResume()` and only show the dialogs required then.
+     *
+     * @param fragmentManager The `FragmentManager` required to search for open dialogs.
+     */
+    @JvmStatic
+    @Deprecated("Only works with deprecated DialogFragment implementations. Should not be needed for MaterialDialogs.")
+    @Suppress("MemberVisibilityCanBePrivate") // Used by implementing app
+    fun dismissAllDialogs(fragmentManager: FragmentManager) {
+
+        val fragments = fragmentManager.fragments
+        for (fragment in fragments) {
+            if (fragment is EnergySettingDialog) {
+                fragment.dismissAllowingStateLoss()
+            }
+            val childFragmentManager = fragment.childFragmentManager
+            @Suppress("DEPRECATION") // Ok as this is called inside the method marked as deprecated
+            dismissAllDialogs(childFragmentManager)
+        }
+    }
+}