diff --git a/demo/app/analysis_options.yaml b/demo/app/analysis_options.yaml
index 61b6c4de..1caa1fad 100644
--- a/demo/app/analysis_options.yaml
+++ b/demo/app/analysis_options.yaml
@@ -23,7 +23,7 @@ linter:
   # producing the lint.
   rules:
     # avoid_print: false  # Uncomment to disable the `avoid_print` rule
-    # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
+    prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
 
 # Additional information about this file can be found at
 # https://dart.dev/guides/language/analysis-options
diff --git a/demo/app/integration_test/openid4ci_test.dart b/demo/app/integration_test/openid4ci_test.dart
index bca882ab..21c8983b 100644
--- a/demo/app/integration_test/openid4ci_test.dart
+++ b/demo/app/integration_test/openid4ci_test.dart
@@ -12,59 +12,59 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() async {
-  print("Init Wallet SDK Plugin");
+  print('Init Wallet SDK Plugin');
   final walletSDKPlugin = WalletSDK();
-  print("Init SDK");
-  const didResolverURI = String.fromEnvironment("DID_RESOLVER_URI");
+  print('Init SDK');
+  const didResolverURI = String.fromEnvironment('DID_RESOLVER_URI');
   await walletSDKPlugin.initSDK(didResolverURI);
-  var didKeyType = "";
+  var didKeyType = '';
   testWidgets('Testing openid4vc with a single credential', (tester) async {
-    const didMethodTypes = String.fromEnvironment("WALLET_DID_METHODS");
+    const didMethodTypes = String.fromEnvironment('WALLET_DID_METHODS');
     var didMethodTypesList = didMethodTypes.split(' ');
 
-    const issuanceURLs = String.fromEnvironment("INITIATE_ISSUANCE_URLS");
+    const issuanceURLs = String.fromEnvironment('INITIATE_ISSUANCE_URLS');
     var issuanceURLsList = issuanceURLs.split(' ');
 
-    const verificationURLs = String.fromEnvironment("INITIATE_VERIFICATION_URLS");
+    const verificationURLs = String.fromEnvironment('INITIATE_VERIFICATION_URLS');
     var verificationURLsList = verificationURLs.split(' ');
 
     for (int i = 0; i < issuanceURLsList.length; i++) {
       String didMethodType = didMethodTypesList[i];
-      print("wallet DID Type : $didMethodType");
-      print("wallet DID Key Type : $didKeyType");
+      print('wallet DID Type : $didMethodType');
+      print('wallet DID Key Type : $didKeyType');
       var didDocData = await walletSDKPlugin.createDID(didMethodTypesList[i], didKeyType);
       final didContent= didDocData.did;
-      print("wallet DID : $didContent");
+      print('wallet DID : $didContent');
 
       String issuanceURL = issuanceURLsList[i];
-      print("issuanceURL : $issuanceURL");
+      print('issuanceURL : $issuanceURL');
 
       var initializeResp = await walletSDKPlugin.initialize(issuanceURL, null);
       var initializeRespEncoded = json.encode(initializeResp!);
       Map<String, dynamic> initializeRespJson = json.decode(initializeRespEncoded);
-      var requirePIN = initializeRespJson["pinRequired"];
-      print("requirePIN: $requirePIN");
+      var requirePIN = initializeRespJson['pinRequired'];
+      print('requirePIN: $requirePIN');
 
-      final credential = await walletSDKPlugin.requestCredential("");
-      debugPrint("content: $credential");
+      final credential = await walletSDKPlugin.requestCredential('');
+      debugPrint('content: $credential');
       for (final p in credential.split('.')) {
-        print("----");
+        print('----');
         print(p);
       }
 
       expect(credential, hasLength(greaterThan(0)));
 
       String verificationURL = verificationURLsList[i];
-      print("verificationURL : $verificationURL");
+      print('verificationURL : $verificationURL');
 
       await walletSDKPlugin
           .processAuthorizationRequest(authorizationRequest: verificationURL);
 
-      print("getSubmissionRequirements");
+      print('getSubmissionRequirements');
 
       final requirements = await walletSDKPlugin.getSubmissionRequirements( storedCredentials: [credential]);
 
-      print("getSubmissionRequirements finished");
+      print('getSubmissionRequirements finished');
 
       expect(requirements, hasLength(equals(1)));
       expect(requirements[0].inputDescriptors, hasLength(equals(1)));
@@ -75,16 +75,16 @@ void main() async {
   });
 
   testWidgets('Testing openid4vc with multiple credentials', (tester) async {
-    const didMethodTypes = String.fromEnvironment("WALLET_DID_METHODS");
+    const didMethodTypes = String.fromEnvironment('WALLET_DID_METHODS');
     var didMethodTypesList = didMethodTypes.split(' ');
     String didMethodType = didMethodTypesList[0];
-    print("wallet DID type : $didMethodType");
-    print("wallet DID Key type : $didKeyType");
+    print('wallet DID type : $didMethodType');
+    print('wallet DID Key type : $didKeyType');
     var didDocData = await walletSDKPlugin.createDID(didMethodTypesList[0], didKeyType);
     var didContent= didDocData.did;
-    print("wallet DID : $didContent");
+    print('wallet DID : $didContent');
 
-    const issuanceURLs = String.fromEnvironment("INITIATE_ISSUANCE_URLS_MULTIPLE_CREDS");
+    const issuanceURLs = String.fromEnvironment('INITIATE_ISSUANCE_URLS_MULTIPLE_CREDS');
     var issuanceURLsList = issuanceURLs.split(' ');
 
     List<String> credentials = [];
@@ -92,31 +92,31 @@ void main() async {
     // Issue multiple credentials
     for (int i = 0; i < issuanceURLsList.length; i++) {
       String issuanceURL = issuanceURLsList[i];
-      print("issuanceURL : $issuanceURL");
+      print('issuanceURL : $issuanceURL');
 
       var initializeResp = await walletSDKPlugin.initialize(issuanceURL, null);
       var initializeRespEncoded = json.encode(initializeResp!);
       Map<String, dynamic> initializeRespJson = json.decode(initializeRespEncoded);
-      var requirePIN = initializeRespJson["pinRequired"];
-      print("requirePIN: $requirePIN");
+      var requirePIN = initializeRespJson['pinRequired'];
+      print('requirePIN: $requirePIN');
 
-      final credential = await walletSDKPlugin.requestCredential("");
+      final credential = await walletSDKPlugin.requestCredential('');
 
       expect(credential, hasLength(greaterThan(0)));
 
       credentials.add(credential);
     }
-    print("issued credentials: $credentials");
+    print('issued credentials: $credentials');
 
-    const verificationURLs = String.fromEnvironment("INITIATE_VERIFICATION_URLS_MULTIPLE_CREDS");
+    const verificationURLs = String.fromEnvironment('INITIATE_VERIFICATION_URLS_MULTIPLE_CREDS');
     var verificationURLsList = verificationURLs.split(' ');
     String verificationURL = verificationURLsList[0];
-    print("verificationURL : $verificationURL");
+    print('verificationURL : $verificationURL');
 
     final matchedCreds = await walletSDKPlugin
         .processAuthorizationRequest(authorizationRequest: verificationURL, storedCredentials: credentials);
 
-    print("matchedCreds : $matchedCreds");
+    print('matchedCreds : $matchedCreds');
 
     expect(matchedCreds, hasLength(equals(3)));
 
@@ -128,32 +128,32 @@ void main() async {
   });
 
   testWidgets('Testing openid4vc with the auth code flow', (tester) async {
-    const didMethodTypes = String.fromEnvironment("WALLET_DID_METHODS");
+    const didMethodTypes = String.fromEnvironment('WALLET_DID_METHODS');
     var didMethodTypesList = didMethodTypes.split(' ');
     String didMethodType = didMethodTypesList[0];
-    print("wallet DID type : $didMethodType");
-    print("wallet DID Key type : $didKeyType");
+    print('wallet DID type : $didMethodType');
+    print('wallet DID Key type : $didKeyType');
     var didDocData = await walletSDKPlugin.createDID(didMethodTypesList[0], didKeyType);
-    print("wallet didDocData : $didDocData");
+    print('wallet didDocData : $didDocData');
     var didContent= didDocData.did;
-    print("wallet DID : $didContent");
+    print('wallet DID : $didContent');
 
-    const issuanceURL = String.fromEnvironment("INITIATE_ISSUANCE_URLS_AUTH_CODE_FLOW");
-    debugPrint("issuanceURLs: $issuanceURL");
+    const issuanceURL = String.fromEnvironment('INITIATE_ISSUANCE_URLS_AUTH_CODE_FLOW');
+    debugPrint('issuanceURLs: $issuanceURL');
 
       var authCodeArgs =   {
-        "scopes": ["openid","profile"],
-        "clientID": "oidc4vc_client",
-        "redirectURI": "http://127.0.0.1/callback"
+        'scopes': ['openid','profile'],
+        'clientID': 'oidc4vc_client',
+        'redirectURI': 'http://127.0.0.1/callback'
       };
 
       var initializeResp = await walletSDKPlugin.initialize(issuanceURL, authCodeArgs);
       var initializeRespEncoded = json.encode(initializeResp!);
       Map<String, dynamic> initializeRespJson = json.decode(initializeRespEncoded);
-      var authorizationURLLink= initializeRespJson["authorizationURLLink"];
-    debugPrint("authorizationURLLink: $authorizationURLLink");
+      var authorizationURLLink= initializeRespJson['authorizationURLLink'];
+    debugPrint('authorizationURLLink: $authorizationURLLink');
     // fetching redirect uri
-    var redirectURI;
+    String redirectURI = '';
     final client = HttpClient();
     var redirectUrl = Uri.parse(authorizationURLLink);
     var request = await client.getUrl(redirectUrl);
@@ -164,14 +164,14 @@ void main() async {
       final location = response.headers.value(HttpHeaders.locationHeader);
       if (location != null) {
         redirectUrl = redirectUrl.resolve(location);
-        if (location.contains("http://127.0.0.1/callback"))
+        if (location.contains('http://127.0.0.1/callback'))
         {
           redirectURI = location;
           break;
         }
-        if (redirectUrl.host.contains("cognito-mock.trustbloc.local")){
-          redirectUrl = Uri.parse(redirectUrl.toString().replaceAll("cognito-mock.trustbloc.local", "localhost"));
-          print("uri updated $redirectUrl");
+        if (redirectUrl.host.contains('cognito-mock.trustbloc.local')){
+          redirectUrl = Uri.parse(redirectUrl.toString().replaceAll('cognito-mock.trustbloc.local', 'localhost'));
+          print('uri updated $redirectUrl');
         }
         request = await client.getUrl(redirectUrl);
         request.followRedirects = false;
@@ -179,12 +179,12 @@ void main() async {
       }
     }
 
-    debugPrint("redirectURI $redirectURI");
+    debugPrint('redirectURI $redirectURI');
 
       final credential = await walletSDKPlugin.requestCredentialWithAuth(redirectURI);
-      debugPrint("content: $credential");
+      debugPrint('content: $credential');
       for (final p in credential.split('.')) {
-        print("----");
+        print('----');
         print(p);
       }
 
diff --git a/demo/app/lib/main.dart b/demo/app/lib/main.dart
index 86e7b5a1..21763cbe 100644
--- a/demo/app/lib/main.dart
+++ b/demo/app/lib/main.dart
@@ -4,7 +4,6 @@ Copyright Gen Digital Inc. All Rights Reserved.
 SPDX-License-Identifier: Apache-2.0
 */
 
-import 'dart:io';
 
 import 'package:app/scenarios/handle_openid_url.dart';
 import 'package:app/widgets/common_logo_appbar.dart';
@@ -22,7 +21,7 @@ final WalletSDKPlugin = WalletSDK();
 
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
-  const didResolverURI = String.fromEnvironment("didResolverURI");
+  const didResolverURI = String.fromEnvironment('didResolverURI');
   await WalletSDKPlugin.initSDK(didResolverURI);
 
   runApp(const MyApp());
diff --git a/demo/app/lib/models/store_credential_data.dart b/demo/app/lib/models/store_credential_data.dart
index 30ef9a0d..38065c85 100644
--- a/demo/app/lib/models/store_credential_data.dart
+++ b/demo/app/lib/models/store_credential_data.dart
@@ -16,7 +16,7 @@ class UserLoginDetails {
 Future<UserLoginDetails> getUser() async {
   SharedPreferences prefs = await SharedPreferences.getInstance();
   final SharedPreferences p = prefs;
-  String? userLoggedIn = p.getString("userLoggedIn");
-  print("userLoginDetails -> $userLoggedIn");
+  String? userLoggedIn = p.getString('userLoggedIn');
+  print('userLoginDetails -> $userLoggedIn');
   return UserLoginDetails(userLoggedIn);
 }
diff --git a/demo/app/lib/scenarios/handle_openid_issuance_flow.dart b/demo/app/lib/scenarios/handle_openid_issuance_flow.dart
index 1e32a8a4..91ef6202 100644
--- a/demo/app/lib/scenarios/handle_openid_issuance_flow.dart
+++ b/demo/app/lib/scenarios/handle_openid_issuance_flow.dart
@@ -18,23 +18,23 @@ import '../views/custom_error.dart';
 void handleOpenIDIssuanceFlow(BuildContext context, String qrCodeURL) async {
   var WalletSDKPlugin = WalletSDK();
   var authCodeArgs;
-  if (qrCodeURL.contains("credential_offer_uri")) {
+  if (qrCodeURL.contains('credential_offer_uri')) {
     authCodeArgs = await parseCredentialOfferUri(qrCodeURL);
-    log("credential offer uri auth code  ${authCodeArgs}");
+    log('credential offer uri auth code  $authCodeArgs');
   } else {
-    if (qrCodeURL.contains("authorization_code")) {
+    if (qrCodeURL.contains('authorization_code')) {
       authCodeArgs = await readIssuerAuthFlowConfig(qrCodeURL);
-      log("auth code arguments fetched from config file $authCodeArgs");
+      log('auth code arguments fetched from config file $authCodeArgs');
       // While fetching auth code args based on issuer key from file, if no key-value pair is found then set the
       // arguments to default scope and redirect url.
       authCodeArgs ??= {
-        "scopes": ["openid", "profile"],
-        "redirectURI": "trustbloc-wallet://openid4vci/authcodeflow/callback"
+        'scopes': ['openid', 'profile'],
+        'redirectURI': 'trustbloc-wallet://openid4vci/authcodeflow/callback'
       };
     }
   }
-  log("qr code url -  $qrCodeURL");
-  var flowTypeData;
+  log('qr code url -  $qrCodeURL');
+  Map<Object?, Object?>? flowTypeData;
   try {
     flowTypeData = await WalletSDKPlugin.initialize(qrCodeURL, authCodeArgs);
   } catch (error) {
@@ -43,22 +43,22 @@ void handleOpenIDIssuanceFlow(BuildContext context, String qrCodeURL) async {
         context,
         MaterialPageRoute(
             builder: (context) => CustomError(
-                 titleBar: "QR Code Scanned",
-                requestErrorTitleMsg: "error while intializing the interaction",
-                requestErrorSubTitleMsg: "${errString}")));
+                 titleBar: 'QR Code Scanned',
+                requestErrorTitleMsg: 'error while intializing the interaction',
+                requestErrorSubTitleMsg: errString)));
     return;
   }
   var flowTypeDataEncoded = json.encode(flowTypeData);
   Map<String, dynamic> responseJson = json.decode(flowTypeDataEncoded);
-  var authorizeResultPinRequired = responseJson["pinRequired"];
-  log("pin required flow -  $authorizeResultPinRequired");
+  var authorizeResultPinRequired = responseJson['pinRequired'];
+  log('pin required flow -  $authorizeResultPinRequired');
   if (authorizeResultPinRequired == true) {
     navigateToIssuancePreviewScreen(context, authorizeResultPinRequired);
     return;
-  } else if (responseJson["authorizationURLLink"] != '') {
+  } else if (responseJson['authorizationURLLink'] != '') {
     // initiate authCode Flow
     log("initiating authCode Flow- ${responseJson["authorizationURLLink"]}");
-    Uri uri = Uri.parse(responseJson["authorizationURLLink"]);
+    Uri uri = Uri.parse(responseJson['authorizationURLLink']);
     navigateToIssuancePreviewScreenAuthFlow(context, uri);
     return;
   } else {
@@ -70,10 +70,10 @@ void handleOpenIDIssuanceFlow(BuildContext context, String qrCodeURL) async {
 readIssuerAuthFlowConfig(String qrCodeURL) async {
   var decodedUri = Uri.decodeComponent(qrCodeURL);
   final uri = Uri.parse(decodedUri);
-  var credentialIssuerKey = json.decode(uri.queryParameters["credential_offer"]!);
+  var credentialIssuerKey = json.decode(uri.queryParameters['credential_offer']!);
   final String response = await rootBundle.loadString('lib/assets/issuerAuthFlowConfig.json');
   final configData = await json.decode(response);
-  return configData[credentialIssuerKey["credential_issuer"]];
+  return configData[credentialIssuerKey['credential_issuer']];
 }
 
 parseCredentialOfferUri(String qrCodeURL) async {
diff --git a/demo/app/lib/scenarios/handle_openid_url.dart b/demo/app/lib/scenarios/handle_openid_url.dart
index 95e7edbc..b04c0335 100644
--- a/demo/app/lib/scenarios/handle_openid_url.dart
+++ b/demo/app/lib/scenarios/handle_openid_url.dart
@@ -5,7 +5,6 @@ SPDX-License-Identifier: Apache-2.0
 */
 
 import 'dart:developer';
-import 'package:app/wallet_sdk/wallet_sdk.dart';
 import 'package:app/scenarios/handle_openid_issuance_flow.dart';
 import 'package:app/scenarios/handle_openid_vp_flow.dart';
 import 'package:app/wallet_sdk/wallet_sdk_model.dart';
@@ -14,7 +13,7 @@ import 'package:flutter/material.dart';
 void handleOpenIDUrl(BuildContext context, String qrCodeURL) async {
   log('received qr code url - $qrCodeURL');
   // Check if the flow is for the verifiable presentation or for issuance.
-  if (!qrCodeURL.contains("openid-vc")) {
+  if (!qrCodeURL.contains('openid-vc')) {
     handleOpenIDIssuanceFlow(context, qrCodeURL);
   } else {
     handleOpenIDVpFlow(context, qrCodeURL);
diff --git a/demo/app/lib/scenarios/handle_openid_vp_flow.dart b/demo/app/lib/scenarios/handle_openid_vp_flow.dart
index 77641095..5357f701 100644
--- a/demo/app/lib/scenarios/handle_openid_vp_flow.dart
+++ b/demo/app/lib/scenarios/handle_openid_vp_flow.dart
@@ -39,7 +39,7 @@ void handleOpenIDVpFlow(BuildContext context, String qrCodeURL) async {
         context,
         MaterialPageRoute(
             builder: (context) =>
-                CustomError(titleBar: "Processing Presentation", requestErrorTitleMsg: error.message!, requestErrorSubTitleMsg: error.details)));
+                CustomError(titleBar: 'Processing Presentation', requestErrorTitleMsg: error.message!, requestErrorSubTitleMsg: error.details)));
   }
   // Get the matched VCIDs from the submission request.
   var getSubmissionRequest = await walletSDKPlugin.getSubmissionRequirements(storedCredentials: credentials);
@@ -48,10 +48,10 @@ void handleOpenIDVpFlow(BuildContext context, String qrCodeURL) async {
     // multiple matched vc ids are found therefore, invoking multiple credential Presentation Preview.
     List<CredentialData> credentialDisplayDataList = [];
     for (var cred in credentials) {
-      log("multi cred flow $submission and ${credentials.length}");
+      log('multi cred flow $submission and ${credentials.length}');
       for (var inputDescriptor in submission.inputDescriptors) {
         Map<String, dynamic> payload = Jwt.parseJwt(cred);
-        if (inputDescriptor.matchedVCsID.contains(payload["jti"])) {
+        if (inputDescriptor.matchedVCsID.contains(payload['jti'])) {
           var credentialDisplayData = storedCredentials
               .where((element) => cred.contains(element.value.rawCredential))
               .map((e) => CredentialData(
@@ -65,12 +65,12 @@ void handleOpenIDVpFlow(BuildContext context, String qrCodeURL) async {
         }
       }
     }
-    navigateToPresentMultiCred(context, credentialDisplayDataList, "Choose ${submission.count} credentials to present");
+    navigateToPresentMultiCred(context, credentialDisplayDataList, 'Choose ${submission.count} credentials to present');
     return;
   } else if (submission.count == 1) {
     var matchedVCsID = submission.inputDescriptors.first.matchedVCsID;
     if (matchedVCsID.length > 1) {
-      log("matched length, more than matched vc ids are found ${matchedVCsID.length}");
+      log('matched length, more than matched vc ids are found ${matchedVCsID.length}');
       var credentialDisplayData = storedCredentials
           .where((element) => credentials.contains(element.value.rawCredential))
           .map((e) => CredentialData(
@@ -83,21 +83,21 @@ void handleOpenIDVpFlow(BuildContext context, String qrCodeURL) async {
       navigateToPresentMultiCredChooseOne(context, credentialDisplayData);
       return;
     } else {
-      log("single matched vc id flow");
-      var credentialDisplayData;
+      log('single matched vc id flow');
+      String credentialDisplayData;
       for (var inputDes in submission.inputDescriptors) {
         for (var matchVC in inputDes.matchedVCs) {
           var credID = (await walletSDKPlugin.getCredID([matchVC]))!;
           var issuerURI = storedCredentials
-              .where((element) => credID!.contains(element.value.credID))
+              .where((element) => credID.contains(element.value.credID))
               .map((e) => e.value.issuerURL)
               .toList();
           var credentialDID =
-              storedCredentials.firstWhere((element) => credID!.contains(element.value.credID)).value.credentialDID;
+              storedCredentials.firstWhere((element) => credID.contains(element.value.credID)).value.credentialDID;
 
-          log("matched issuerURI found: ${issuerURI}");
-          credentialDisplayData = await walletSDKPlugin.serializeDisplayData([matchVC], issuerURI.first);
-          log("credentialDisplayData -> $credentialDisplayData");
+          log('matched issuerURI found: $issuerURI');
+          credentialDisplayData = (await walletSDKPlugin.serializeDisplayData([matchVC], issuerURI.first))!;
+          log('credentialDisplayData -> $credentialDisplayData');
           navigateToPresentationPreviewScreen(
               context,
               CredentialData(
diff --git a/demo/app/lib/services/config_service.dart b/demo/app/lib/services/config_service.dart
index ae69f476..4ba6266d 100644
--- a/demo/app/lib/services/config_service.dart
+++ b/demo/app/lib/services/config_service.dart
@@ -18,7 +18,7 @@ class ConfigService{
       connectIssuerConfigList.add(connectIssuerConfig);
     });
 
-    log("decodedResponse $configResponseDecoded");
+    log('decodedResponse $configResponseDecoded');
     return connectIssuerConfigList;
   }
 }
\ No newline at end of file
diff --git a/demo/app/lib/services/storage_service.dart b/demo/app/lib/services/storage_service.dart
index bb9e020c..94e91965 100644
--- a/demo/app/lib/services/storage_service.dart
+++ b/demo/app/lib/services/storage_service.dart
@@ -3,7 +3,6 @@ import 'dart:core';
 
 import 'package:app/models/activity_data_object.dart';
 import 'package:app/models/credential_data_object.dart';
-import 'package:app/models/activity_logger.dart';
 import 'package:app/models/credential_data.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
@@ -18,13 +17,13 @@ class StorageService {
 
 
   Future<void> addCredential(CredentialDataObject newItem) async {
-    debugPrint("Adding new data having key ${newItem.key}");
+    debugPrint('Adding new data having key ${newItem.key}');
     await _secureStorage.write(
         key: newItem.key, value: json.encode(newItem.value.toJson()), aOptions: _getAndroidOptions());
   }
 
   Future<List<CredentialDataObject>> retrieveCredentials(String username) async {
-    debugPrint("Retrieve all secured data");
+    debugPrint('Retrieve all secured data');
     var allData = await _secureStorage.readAll(aOptions: _getAndroidOptions());
     List<CredentialDataObject> list = allData.entries
         .where((e) => e.key.contains(username))
@@ -34,13 +33,13 @@ class StorageService {
   }
 
   Future<void> addActivities(ActivityDataObj activityObj) async {
-    debugPrint("Adding new data having key ${activityObj.key}");
+    debugPrint('Adding new data having key ${activityObj.key}');
     await _secureStorage.write(
         key: activityObj.key, value: jsonEncode(activityObj.value), aOptions: _getAndroidOptions());
   }
 
   Future<List> retrieveActivities(String credID) async {
-    debugPrint("Retrieve stored activities $credID");
+    debugPrint('Retrieve stored activities $credID');
     var allData = await _secureStorage.readAll(aOptions: _getAndroidOptions());
     List list = allData.entries
         .where((e) => e.key.contains(credID))
@@ -50,24 +49,24 @@ class StorageService {
   }
 
   Future<void> deleteData(CredentialDataObject item) async {
-    debugPrint("Deleting data having key ${item.key}");
+    debugPrint('Deleting data having key ${item.key}');
     await _secureStorage.delete(key: item.key, aOptions: _getAndroidOptions());
   }
 
   Future<List<StorageItem>> retrieveAll() async {
-    debugPrint("Retrieve all secured data");
+    debugPrint('Retrieve all secured data');
     var allData = await _secureStorage.readAll(aOptions: _getAndroidOptions());
     List<StorageItem> list = allData.entries.map((e) => StorageItem(e.key, e.value)).toList();
     return list;
   }
 
   Future<void> deleteAllData() async {
-    debugPrint("Deleting all secured data");
+    debugPrint('Deleting all secured data');
     await _secureStorage.deleteAll(aOptions: _getAndroidOptions());
   }
 
   Future<bool> containsKeyInSecureData(String key) async {
-    debugPrint("Checking data for the key $key");
+    debugPrint('Checking data for the key $key');
     var containsKey = await _secureStorage.containsKey(key: key, aOptions: _getAndroidOptions());
     return containsKey;
   }
diff --git a/demo/app/lib/views/credential_details.dart b/demo/app/lib/views/credential_details.dart
index 4feac74c..35bd734f 100644
--- a/demo/app/lib/views/credential_details.dart
+++ b/demo/app/lib/views/credential_details.dart
@@ -65,13 +65,13 @@ class CredentialDetailsState extends State<CredentialDetails> {
   }
 
   getCredentialDID(){
-    return SelectableText(widget.credentialData.credentialDID!);
+    return SelectableText(widget.credentialData.credentialDID);
   }
 
   getDidDocument() async {
     final Future<SharedPreferences> prefs = SharedPreferences.getInstance();
     final SharedPreferences pref = await prefs;
-    var userDIDDoc = pref.getString("userDIDDoc");
+    var userDIDDoc = pref.getString('userDIDDoc');
     final parsedJson = json.decode(userDIDDoc!);
     didDoc = const JsonEncoder.withIndent('  ').convert(parsedJson);
   }
@@ -105,7 +105,7 @@ class CredentialDetailsState extends State<CredentialDetails> {
                       child: SizedBox(
                         width: 50,
                         child: Text(
-                          "Details",
+                          'Details',
                           textAlign: TextAlign.start,
                         ),
                       ),
@@ -116,7 +116,7 @@ class CredentialDetailsState extends State<CredentialDetails> {
                       child: SizedBox(
                         width: 150,
                         child: Text(
-                          "Raw",
+                          'Raw',
                           textAlign: TextAlign.start,
                         ),
                       ),
@@ -126,18 +126,18 @@ class CredentialDetailsState extends State<CredentialDetails> {
                       child: SizedBox(
                       width: 60,
                       child: Text(
-                        "Activity",
+                        'Activity',
                         textAlign: TextAlign.start,
                         textScaleFactor:1.0,
                       ),
                     ),
                     ),
                    Visibility(
-                    visible: isSwitched!=null?isSwitched!:false,
+                    visible: isSwitched ?? false,
                      child: const Tab(  child: SizedBox(
                       width: 50,
                       child: Text(
-                        "DID",
+                        'DID',
                         textAlign: TextAlign.start,
                       ),
                      ),
@@ -194,16 +194,16 @@ class CredentialDetailsState extends State<CredentialDetails> {
                                       title: Text(
                                         resp.date,
                                         textAlign: TextAlign.start,
-                                        style: TextStyle(fontSize: 14.0),
+                                        style: const TextStyle(fontSize: 14.0),
                                       ),
                                       subtitle: resp.operation == 'oidc-issuance' ? Text(
-                                        "Issued by: ${resp.issuedBy}",
+                                        'Issued by: ${resp.issuedBy}',
                                         textAlign: TextAlign.start,
-                                        style: TextStyle(fontSize: 13.0, color: Colors.blue),
+                                        style: const TextStyle(fontSize: 13.0, color: Colors.blue),
                                       ) : Text(
-                                        "Presented to: ${resp.issuedBy!}",
+                                        'Presented to: ${resp.issuedBy}',
                                         textAlign: TextAlign.start,
-                                        style: TextStyle(fontSize: 13.0, color: Colors.purple),
+                                        style: const TextStyle(fontSize: 13.0, color: Colors.purple),
                                       ),
                                       leading: resp.status == 'success' ? IconButton(
                                         icon: const Icon(Icons.check_circle, size: 32, color: Color(0xff66BB6A)),
@@ -236,7 +236,7 @@ class CredentialDetailsState extends State<CredentialDetails> {
                                       const Padding(
                                           padding:EdgeInsets.all(8.0),
                                           child:  Text(
-                                            "DID",
+                                            'DID',
                                             style: TextStyle(
                                               fontSize: 16,
                                               color: Color(0xff190C21),
@@ -250,7 +250,7 @@ class CredentialDetailsState extends State<CredentialDetails> {
                                       const Padding(
                                           padding:EdgeInsets.all(8.0),
                                           child:  Text(
-                                            "DidDocument",
+                                            'DidDocument',
                                             style: TextStyle(
                                               fontSize: 16,
                                               color: Color(0xff190C21),
diff --git a/demo/app/lib/views/credential_list.dart b/demo/app/lib/views/credential_list.dart
index 3f523cfa..8b9eb724 100644
--- a/demo/app/lib/views/credential_list.dart
+++ b/demo/app/lib/views/credential_list.dart
@@ -32,8 +32,8 @@ class _CredentialListState extends State<CredentialList> {
   void initList() async {
     SharedPreferences prefs = await SharedPreferences.getInstance();
     final SharedPreferences p = prefs;
-    username = p.getString("userLoggedIn");
-    log("list - $username");
+    username = p.getString('userLoggedIn');
+    log('list - $username');
     _credentialList = await _storageService.retrieveCredentials(username!);
     if (_credentialList.isEmpty) {
       _loading = true;
@@ -63,7 +63,7 @@ class _CredentialListState extends State<CredentialList> {
               child: _loading
                   ? const CircularProgressIndicator()
                   : _credentialList.isEmpty
-                  ? const Text("No credentials found")
+                  ? const Text('No credentials found')
                   : ListView.builder(
                   itemCount: _credentialList.length,
                   padding: const EdgeInsets.symmetric(horizontal: 8),
diff --git a/demo/app/lib/views/credential_preview.dart b/demo/app/lib/views/credential_preview.dart
index a0969b84..3ddc1531 100644
--- a/demo/app/lib/views/credential_preview.dart
+++ b/demo/app/lib/views/credential_preview.dart
@@ -1,5 +1,3 @@
-import 'dart:convert';
-import 'dart:developer';
 import 'package:app/main.dart';
 import 'package:app/models/credential_data.dart';
 import 'package:app/views/credential_added.dart';
@@ -25,7 +23,7 @@ class CredentialPreviewState extends State<CredentialPreview> {
   final StorageService _storageService = StorageService();
   var uuid = const Uuid();
   late final String userLoggedIn;
-  String issuerDisplayData = "";
+  String issuerDisplayData = '';
   bool verifiedDomain = true;
   late String serviceURL = '';
   String? issuerID;
@@ -117,7 +115,7 @@ class CredentialPreviewState extends State<CredentialPreview> {
             child:  Text(
                 textAlign: TextAlign.center,
                 style: TextStyle(fontSize: 18, color: Colors.black),
-                "wants to issue the credential"),
+                'wants to issue the credential'),
           ),
           CredentialCard(credentialData: widget.credentialData, isDashboardWidget: false, isDetailArrowRequired: false),
           Expanded(
@@ -142,7 +140,7 @@ class CredentialPreviewState extends State<CredentialPreview> {
                     ),
                     PrimaryButton(
                         onPressed: () async {
-                            _storageService.addCredential(CredentialDataObject("$userLoggedIn-${uuid.v1()}", widget.credentialData));
+                            _storageService.addCredential(CredentialDataObject('$userLoggedIn-${uuid.v1()}', widget.credentialData));
                             _navigateToCredentialAdded();
                         },
                         width: double.infinity,
diff --git a/demo/app/lib/views/credential_shared.dart b/demo/app/lib/views/credential_shared.dart
index 8bf292a1..b5bb55dc 100644
--- a/demo/app/lib/views/credential_shared.dart
+++ b/demo/app/lib/views/credential_shared.dart
@@ -6,7 +6,7 @@ import 'package:app/views/dashboard.dart';
 class CredentialShared extends StatefulWidget {
   final String? verifierName;
   final List<CredentialData> credentialData;
-  CredentialShared({super.key, this.verifierName, required this.credentialData,});
+  const CredentialShared({super.key, this.verifierName, required this.credentialData,});
 
   @override
   State<CredentialShared> createState() => CredentialSharedState ();
@@ -57,7 +57,7 @@ class CredentialSharedState extends State<CredentialShared> {
               ],
             ),
             title:  const Text('Success',textAlign: TextAlign.left, style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
-            subtitle: Text("Credentials have been shared with ${widget.verifierName}", style: const TextStyle(fontSize: 14, fontWeight: FontWeight.normal)),
+            subtitle: Text('Credentials have been shared with ${widget.verifierName}', style: const TextStyle(fontSize: 14, fontWeight: FontWeight.normal)),
           ),
           Expanded(
             child: ListView.builder(
diff --git a/demo/app/lib/views/handle_redirect_uri.dart b/demo/app/lib/views/handle_redirect_uri.dart
index 47ec37ab..38b8ca18 100644
--- a/demo/app/lib/views/handle_redirect_uri.dart
+++ b/demo/app/lib/views/handle_redirect_uri.dart
@@ -8,7 +8,6 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 import 'dart:developer';
-import 'dart:convert';
 import 'package:app/wallet_sdk/wallet_sdk_mobile.dart';
 import 'package:app/services/storage_service.dart';
 import 'package:shared_preferences/shared_preferences.dart';
@@ -55,9 +54,9 @@ class HandleRedirectUriState extends State<HandleRedirectUri> {
   Future<String?> _createDid() async {
     final SharedPreferences pref = await prefs;
     var didType = pref.getString('didType');
-    didType = didType ?? "ion";
+    didType = didType ?? 'ion';
     var keyType = pref.getString('keyType');
-    keyType = keyType ?? "ED25519";
+    keyType = keyType ?? 'ED25519';
     var didResolution = await WalletSDKPlugin.createDID(didType, keyType);
     var didID = didResolution.did;
     setState(() {
@@ -74,29 +73,29 @@ class HandleRedirectUriState extends State<HandleRedirectUri> {
     pref.setString('userDIDDoc', userDIDDoc);
     if (_redirectUri != null) {
       try {
-        if (widget.flowType == "issuer-initiated-flow") {
-          log("_redirectUri.toString() ${_redirectUri.toString()}");
+        if (widget.flowType == 'issuer-initiated-flow') {
+          log('_redirectUri.toString() ${_redirectUri.toString()}');
           var credentials = await WalletSDKPlugin.requestCredentialWithAuth(_redirectUri.toString());
           var issuerURI = await WalletSDKPlugin.issuerURI();
           var serializedDisplayData = await WalletSDKPlugin.serializeDisplayData([credentials], issuerURI!);
-          log("serializedDisplayData -> $serializedDisplayData");
+          log('serializedDisplayData -> $serializedDisplayData');
           var activities = await WalletSDKPlugin.storeActivityLogger();
           var credID = await WalletSDKPlugin.getCredID([credentials]);
           await _storageService.addActivities(ActivityDataObj(credID!, activities));
-          pref.setString("credID", credID);
+          pref.setString('credID', credID);
           _navigateToCredPreviewScreen(credentials, issuerURI, serializedDisplayData!, userDIDId, credID);
         } else {
-          log("_redirectUri.toString() ${_redirectUri.toString()}");
+          log('_redirectUri.toString() ${_redirectUri.toString()}');
           var credentials = await WalletSDKPlugin.requestCredentialWithWalletInitiatedFlow(_redirectUri.toString());
           var issuerURI = widget.issuerURI;
           var serializedDisplayData = await WalletSDKPlugin.serializeDisplayData([credentials], issuerURI!);
-          log("serializedDisplayData -> $serializedDisplayData");
+          log('serializedDisplayData -> $serializedDisplayData');
           // TODO: Issue-518 Add activity logger support for wallet-initiated-flow
-          _navigateToCredPreviewScreen(credentials, issuerURI, serializedDisplayData!, userDIDId, "");
+          _navigateToCredPreviewScreen(credentials, issuerURI, serializedDisplayData!, userDIDId, '');
         }
       } catch (error) {
-        log("error -> ${error.toString()}");
-        if (error.toString().contains("UKN2-000") || error.toString().contains("OCI1-0008")) {
+        log('error -> ${error.toString()}');
+        if (error.toString().contains('UKN2-000') || error.toString().contains('OCI1-0008')) {
           SizedBox(
             height: MediaQuery.of(context).size.height / 1.9,
             child: const Center(
@@ -108,8 +107,8 @@ class HandleRedirectUriState extends State<HandleRedirectUri> {
               context,
               MaterialPageRoute(
                   builder: (context) => CustomError(
-                      titleBar: "Redirect URI",
-                      requestErrorTitleMsg: "Redirect uri error", requestErrorSubTitleMsg: error.toString())));
+                      titleBar: 'Redirect URI',
+                      requestErrorTitleMsg: 'Redirect uri error', requestErrorSubTitleMsg: error.toString())));
         }
       }
     }
@@ -140,9 +139,9 @@ class HandleRedirectUriState extends State<HandleRedirectUri> {
 
   _handleIncomingLinks() async {
     if (!kIsWeb) {
-      _sub = await uriLinkStream.listen((Uri? uri) {
+      _sub = uriLinkStream.listen((Uri? uri) {
         if (!mounted) return;
-        log("received redirect uri $uri");
+        log('received redirect uri $uri');
         setState(() {
           _redirectUri = uri;
           _err = null;
diff --git a/demo/app/lib/views/issuance_preview.dart b/demo/app/lib/views/issuance_preview.dart
index 30c2b755..20964b2b 100644
--- a/demo/app/lib/views/issuance_preview.dart
+++ b/demo/app/lib/views/issuance_preview.dart
@@ -4,7 +4,6 @@ Copyright Gen Digital Inc. All Rights Reserved.
 SPDX-License-Identifier: Apache-2.0
 */
 
-import 'dart:convert';
 import 'dart:developer';
 
 import 'package:app/main.dart';
@@ -34,9 +33,9 @@ class IssuancePreview extends StatefulWidget {
 }
 
 class IssuancePreviewState extends State<IssuancePreview> {
-  String issuerDisplayName = "";
-  String credentialIssuer = "";
-  String credentialDisplayName = "";
+  String issuerDisplayName = '';
+  String credentialIssuer = '';
+  String credentialDisplayName = '';
   String backgroundColor = '';
   String issuerDisplayURL = '';
   String textColor = '';
@@ -86,7 +85,7 @@ class IssuancePreviewState extends State<IssuancePreview> {
               child: Text(
                   textAlign: TextAlign.center,
                   style: TextStyle(fontSize: 18, color: Colors.black),
-                  "Add this credential ?"),
+                  'Add this credential ?'),
             ),
             const SizedBox(height: 30),
             CachedNetworkImage(
@@ -216,7 +215,7 @@ class IssuancePreviewState extends State<IssuancePreview> {
 
   void navigateToAuthFlow(BuildContext context, Uri uri) async {
     Navigator.of(context)
-        .push(MaterialPageRoute(builder: (context) => HandleRedirectUri(uri, "issuer-initiated-flow", "")));
+        .push(MaterialPageRoute(builder: (context) => HandleRedirectUri(uri, 'issuer-initiated-flow', '')));
   }
 
   void navigateToWithoutPinFlow(BuildContext context) async {
@@ -234,13 +233,13 @@ class IssuancePreviewState extends State<IssuancePreview> {
     var didType = pref.getString('didType');
     var keyType = pref.getString('keyType');
     // choosing default if no selection is made
-    didType = didType ?? "ion";
-    keyType = keyType ?? "ED25519";
+    didType = didType ?? 'ion';
+    keyType = keyType ?? 'ED25519';
 
     var didResolution = await WalletSDKPlugin.createDID(didType, keyType);
     var didID = didResolution.did;
     var didDoc = didResolution.didDoc;
-    log("created didID :$didID");
+    log('created didID :$didID');
 
     pref.setString('userDID', didID);
     pref.setString('userDIDDoc', didDoc);
@@ -253,7 +252,7 @@ class IssuancePreviewState extends State<IssuancePreview> {
 
     var credID = await WalletSDKPlugin.getCredID([credentials]);
 
-    log("activities and credID handle open id  -$activities and $credID");
+    log('activities and credID handle open id  -$activities and $credID');
     storageService.addActivities(ActivityDataObj(credID!, activities));
 
     return CredentialData(
diff --git a/demo/app/lib/views/otp.dart b/demo/app/lib/views/otp.dart
index 18f7007b..5f10c948 100644
--- a/demo/app/lib/views/otp.dart
+++ b/demo/app/lib/views/otp.dart
@@ -1,4 +1,3 @@
-import 'dart:convert';
 import 'dart:developer';
 
 import 'package:app/models/activity_data_object.dart';
@@ -33,9 +32,9 @@ class _OTPPage extends State<OTP> {
   Future<String?> _createDid() async {
     final SharedPreferences pref = await prefs;
     var didType = pref.getString('didType');
-    didType = didType ?? "ion";
+    didType = didType ?? 'ion';
     var keyType = pref.getString('keyType');
-    keyType = keyType ?? "ED25519";
+    keyType = keyType ?? 'ED25519';
     var didResolution = await WalletSDKPlugin.createDID(didType, keyType);
     var didID = didResolution.did;
     setState(() {
@@ -186,30 +185,30 @@ class _OTPPage extends State<OTP> {
                                 String? issuerURI = await WalletSDKPlugin.issuerURI();
                                 serializeDisplayData =
                                 await WalletSDKPlugin.serializeDisplayData([credentials], issuerURI!);
-                                log("serializeDisplayData -> $serializeDisplayData");
+                                log('serializeDisplayData -> $serializeDisplayData');
                                 var activities = await WalletSDKPlugin.storeActivityLogger();
                                 var credID = await WalletSDKPlugin.getCredID([credentials]);
-                                log("activities and credID -$activities and $credID");
+                                log('activities and credID -$activities and $credID');
                                 _storageService.addActivities(ActivityDataObj(credID!, activities));
-                                pref.setString("credID", credID);
+                                pref.setString('credID', credID);
                                 _navigateToCredPreviewScreen(
                                     credentials, issuerURI, serializeDisplayData!, userDIDId, credID);
                               } catch (err) {
                                 String errorMessage = err.toString();
-                                log("errorMessage-> $errorMessage");
+                                log('errorMessage-> $errorMessage');
                                 if (err is PlatformException && err.message != null && err.message!.isNotEmpty) {
-                                  log("err.details-> ${err.details}");
+                                  log('err.details-> ${err.details}');
                                   var resp =
                                   await WalletSDKPlugin.parseWalletSDKError(localizedErrorMessage: err.details);
-                                  log("resp-> $resp");
-                                  (resp.category == "INVALID_GRANT")
+                                  log('resp-> $resp');
+                                  (resp.category == 'INVALID_GRANT')
                                       ? {
-                                    errorMessage = "Try re-entering the PIN or scan a new QR code",
+                                    errorMessage = 'Try re-entering the PIN or scan a new QR code',
                                     _requestErrorDetailMsg = resp.details
                                   }
-                                      : (resp.category == "INVALID_TOKEN")
+                                      : (resp.category == 'INVALID_TOKEN')
                                       ? {
-                                    errorMessage = "Try scanning a new QR code",
+                                    errorMessage = 'Try scanning a new QR code',
                                     _requestErrorDetailMsg = resp.details
                                   }
                                       : {errorMessage = resp.details, _requestErrorDetailMsg = resp.traceID};
diff --git a/demo/app/lib/views/presentation_preview.dart b/demo/app/lib/views/presentation_preview.dart
index d634576b..fdf268a1 100644
--- a/demo/app/lib/views/presentation_preview.dart
+++ b/demo/app/lib/views/presentation_preview.dart
@@ -42,7 +42,7 @@ class PresentationPreviewState extends State<PresentationPreview> {
     super.initState();
     WidgetsBinding.instance.addPostFrameCallback((timeStamp) async {
       final verifiedDisplayData = await WalletSDKPlugin.getVerifierDisplayData();
-      log("verifiedDisplayData ${verifiedDisplayData.logoURI}");
+      log('verifiedDisplayData ${verifiedDisplayData.logoURI}');
       var resp = await WalletSDKPlugin.wellKnownDidConfig(verifiedDisplayData.did);
       setState(() {
         verifierName = verifiedDisplayData.name;
@@ -72,7 +72,7 @@ class PresentationPreviewState extends State<PresentationPreview> {
                 leading: verifierLogoURL == ''
                     ? const SizedBox.shrink()
                     : CachedNetworkImage(
-                        imageUrl: verifierLogoURL!,
+                        imageUrl: verifierLogoURL,
                         placeholder: (context, url) => const CircularProgressIndicator(),
                         errorWidget: (context, url, error) =>
                             Image.asset('lib/assets/images/credLogo.png', fit: BoxFit.contain),
@@ -81,11 +81,11 @@ class PresentationPreviewState extends State<PresentationPreview> {
                         fit: BoxFit.contain,
                       ),
                 title: Text(verifierName, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
-                subtitle: Text(serviceURL != "" ? serviceURL : 'verifier.com',
+                subtitle: Text(serviceURL != '' ? serviceURL : 'verifier.com',
                     style: const TextStyle(fontSize: 12, fontWeight: FontWeight.normal)),
                 trailing: FittedBox(
                     child: verifiedDomain
-                        ? Row(children: [
+                        ? const Row(children: [
                             Text.rich(
                               textAlign: TextAlign.center,
                               TextSpan(
@@ -108,7 +108,7 @@ class PresentationPreviewState extends State<PresentationPreview> {
                               ),
                             ),
                           ])
-                        : Row(
+                        : const Row(
                             children: [
                               Text.rich(
                                 textAlign: TextAlign.center,
@@ -163,15 +163,15 @@ class PresentationPreviewState extends State<PresentationPreview> {
                                   context,
                                   MaterialPageRoute(
                                       builder: (context) => CustomError(
-                                          titleBar: "Presentation Preview",
-                                          requestErrorTitleMsg: "error while presenting credential",
-                                          requestErrorSubTitleMsg: "${errString}")));
+                                          titleBar: 'Presentation Preview',
+                                          requestErrorTitleMsg: 'error while presenting credential',
+                                          requestErrorSubTitleMsg: errString)));
                               return;
                             }
                             var activities = await WalletSDKPlugin.storeActivityLogger();
                             var credID = pref.getString('credID');
                             _storageService.addActivities(ActivityDataObj(credID!, activities));
-                            _navigateToCredentialShareSuccess(verifierName!);
+                            _navigateToCredentialShareSuccess(verifierName);
                           },
                           width: double.infinity,
                           child: const Text('Share Credential', style: TextStyle(fontSize: 16, color: Colors.white))),
diff --git a/demo/app/lib/views/presentation_preview_multi_cred.dart b/demo/app/lib/views/presentation_preview_multi_cred.dart
index 0d2bc4af..90a0db2e 100644
--- a/demo/app/lib/views/presentation_preview_multi_cred.dart
+++ b/demo/app/lib/views/presentation_preview_multi_cred.dart
@@ -45,7 +45,7 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
   @override
   void initState() {
     super.initState();
-    WidgetsBinding.instance?.addPostFrameCallback((timeStamp) async {
+    WidgetsBinding.instance.addPostFrameCallback((timeStamp) async {
       final verifiedDisplayData = await WalletSDKPlugin.getVerifierDisplayData();
 
       var resp = await WalletSDKPlugin.wellKnownDidConfig(verifiedDisplayData.did);
@@ -78,7 +78,7 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
                 leading: verifierLogoURL == ''
                     ? const SizedBox.shrink()
                     : CachedNetworkImage(
-                        imageUrl: verifierLogoURL!,
+                        imageUrl: verifierLogoURL,
                         placeholder: (context, url) => const CircularProgressIndicator(),
                         errorWidget: (context, url, error) =>
                             Image.asset('lib/assets/images/credLogo.png', fit: BoxFit.contain),
@@ -87,11 +87,11 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
                         fit: BoxFit.contain,
                       ),
                 title: Text(verifierName, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
-                subtitle: Text(serviceURL != "" ? serviceURL : 'verifier.com',
+                subtitle: Text(serviceURL != '' ? serviceURL : 'verifier.com',
                     style: const TextStyle(fontSize: 12, fontWeight: FontWeight.normal)),
                 trailing: FittedBox(
                     child: verifiedDomain
-                        ? Row(children: [
+                        ? const Row(children: [
                             Text.rich(
                               textAlign: TextAlign.center,
                               TextSpan(
@@ -114,7 +114,7 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
                               ),
                             ),
                           ])
-                        : Row(
+                        : const Row(
                             children: [
                               Text.rich(
                                 textAlign: TextAlign.center,
@@ -168,17 +168,17 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
                     value: selectedIndexes.contains(index),
                     onChanged: (value) {
                       setState(() {
-                        log("selected item ${selectedIndexes.contains(index)}");
+                        log('selected item ${selectedIndexes.contains(index)}');
                         if (selectedIndexes.contains(index)) {
                           selectedIndexes.remove(index);
                           multipleSelected.remove(checkListItems[index].rawCredential);
-                          log("multiple selected removing ${multipleSelected}");
+                          log('multiple selected removing $multipleSelected');
                           selectedCredentialData.removeAt(index);
                           setState(() => rememberMe = value!);
                         } else {
                           selectedIndexes.add(index);
                           multipleSelected.add(checkListItems[index].rawCredential);
-                          log("multiple selected adding ${multipleSelected}");
+                          log('multiple selected adding $multipleSelected');
                           selectedCredentialData.add(CredentialData(
                               rawCredential: checkListItems[index].rawCredential,
                               credentialDisplayData: checkListItems[index].credentialDisplayData,
@@ -200,7 +200,7 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
                   ? Container(
                       decoration: BoxDecoration(color: Colors.redAccent, borderRadius: BorderRadius.circular(8.0)),
                       child: Padding(
-                          padding: EdgeInsets.all(12),
+                          padding: const EdgeInsets.all(12),
                           child: SelectableText(
                             widget.infoData!,
                             style: TextStyle(fontWeight: FontWeight.bold, color: Colors.white.withOpacity(0.8)),
@@ -217,25 +217,26 @@ class PresentationPreviewMultiCredCheckState extends State<PresentationPreviewMu
                       ),
                       PrimaryButton(
                           onPressed: () async {
-                            if (rememberMe != true)
+                            if (rememberMe != true) {
                               setState(() => showErrorMessage = true);
-                            else
+                            } else {
                               setState(() => showErrorMessage = false);
+                            }
                             final SharedPreferences pref = await prefs;
                             try {
                               await WalletSDKPlugin.presentCredential(
                                   selectedCredentials: multipleSelected.cast<String>());
                             } catch (error) {
                               log(error.toString());
-                              if (!error.toString().contains("OVP1-0002")) {
+                              if (!error.toString().contains('OVP1-0002')) {
                                 var errString = error.toString().replaceAll(r'\', '');
                                 Navigator.push(
                                     context,
                                     MaterialPageRoute(
                                         builder: (context) => CustomError(
-                                            titleBar: "Multi Presentation Preview",
-                                            requestErrorTitleMsg: "error while presenting credential",
-                                            requestErrorSubTitleMsg: "${errString}")));
+                                            titleBar: 'Multi Presentation Preview',
+                                            requestErrorTitleMsg: 'error while presenting credential',
+                                            requestErrorSubTitleMsg: errString)));
                                 return;
                               } else {
                                 await WalletSDKPlugin.presentCredential(
diff --git a/demo/app/lib/views/presentation_preview_multi_cred_radio.dart b/demo/app/lib/views/presentation_preview_multi_cred_radio.dart
index 3848f421..4ecc1822 100644
--- a/demo/app/lib/views/presentation_preview_multi_cred_radio.dart
+++ b/demo/app/lib/views/presentation_preview_multi_cred_radio.dart
@@ -37,7 +37,7 @@ class PresentationPreviewMultiCredState extends State<PresentationPreviewMultiCr
   @override
   void initState() {
     super.initState();
-    WidgetsBinding.instance?.addPostFrameCallback((timeStamp) async {
+    WidgetsBinding.instance.addPostFrameCallback((timeStamp) async {
       final verifiedDisplayData = await WalletSDKPlugin.getVerifierDisplayData();
       var resp = await WalletSDKPlugin.wellKnownDidConfig(verifiedDisplayData.did);
       setState(() {
@@ -75,7 +75,7 @@ class PresentationPreviewMultiCredState extends State<PresentationPreviewMultiCr
                 leading: verifierLogoURL == ''
                     ? const SizedBox.shrink()
                     : CachedNetworkImage(
-                        imageUrl: verifierLogoURL!,
+                        imageUrl: verifierLogoURL,
                         placeholder: (context, url) => const CircularProgressIndicator(),
                         errorWidget: (context, url, error) =>
                             Image.asset('lib/assets/images/credLogo.png', fit: BoxFit.contain),
@@ -84,11 +84,11 @@ class PresentationPreviewMultiCredState extends State<PresentationPreviewMultiCr
                         fit: BoxFit.contain,
                       ),
                 title: Text(verifierName, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
-                subtitle: Text(serviceURL != "" ? serviceURL : 'verifier.com',
+                subtitle: Text(serviceURL != '' ? serviceURL : 'verifier.com',
                     style: const TextStyle(fontSize: 12, fontWeight: FontWeight.normal)),
                 trailing: FittedBox(
                     child: verifiedDomain
-                        ?  Row(children: [
+                        ?  const Row(children: [
                             Text.rich(
                               textAlign: TextAlign.center,
                               TextSpan(
@@ -111,7 +111,7 @@ class PresentationPreviewMultiCredState extends State<PresentationPreviewMultiCr
                               ),
                             ),
                           ])
-                        :  Row(
+                        :  const Row(
                             children: [
                               Text.rich(
                                 textAlign: TextAlign.center,
@@ -148,7 +148,7 @@ class PresentationPreviewMultiCredState extends State<PresentationPreviewMultiCr
                   value: i,
                   groupValue: selectedRadio,
                   onChanged: (val) {
-                    print("Radio $val");
+                    print('Radio $val');
                     selectedCredentialData = widget.credentialData[i];
                     setSelectedRadio(val!);
                   },
diff --git a/demo/app/lib/views/settings.dart b/demo/app/lib/views/settings.dart
index 5dc29a52..c83ae3e2 100644
--- a/demo/app/lib/views/settings.dart
+++ b/demo/app/lib/views/settings.dart
@@ -104,7 +104,7 @@ class SettingsState extends State<Settings> {
               SwitchListTile(
                 value: isSwitched,
                 contentPadding: EdgeInsets.zero,
-                title: const Text("Dev Mode", style: TextStyle(color: Color(0xff190C21),
+                title: const Text('Dev Mode', style: TextStyle(color: Color(0xff190C21),
                     fontWeight: FontWeight.w700,
                     fontFamily: 'SF Pro',
                     fontSize: 14,
@@ -120,8 +120,8 @@ class SettingsState extends State<Settings> {
               ),
               DropdownButtonFormField<String>(
                 value: selectedDIDType,
-                decoration: InputDecoration(
-                  labelText: "Select DID Method",
+                decoration: const InputDecoration(
+                  labelText: 'Select DID Method',
                   filled: false,
                 ),
                 icon: const Icon(Icons.arrow_drop_down),
@@ -143,8 +143,8 @@ class SettingsState extends State<Settings> {
               ),
               DropdownButtonFormField<String>(
                 value: selectedKeyType,
-                decoration: InputDecoration(
-                  labelText: "Select Key Type",
+                decoration: const InputDecoration(
+                  labelText: 'Select Key Type',
                   filled: false,
                 ),
                 icon: const Icon(Icons.arrow_drop_down),
@@ -232,14 +232,14 @@ class SettingsState extends State<Settings> {
     var versionDetailResp = await walletSDKPlugin.getVersionDetails();
     var didDocEncoded = json.encode(versionDetailResp!);
     Map<String, dynamic> responseJson = json.decode(didDocEncoded);
-    walletSDKVersion = responseJson["walletSDKVersion"];
-    gitRevision = responseJson["gitRevision"];
-    buildTimeRev = responseJson["buildTimeRev"];
+    walletSDKVersion = responseJson['walletSDKVersion'];
+    gitRevision = responseJson['gitRevision'];
+    buildTimeRev = responseJson['buildTimeRev'];
   }
 
   getUserDetails() async {
     UserLoginDetails userLoginDetails = await getUser();
-    log("userLoginDetails -> $userLoginDetails");
+    log('userLoginDetails -> $userLoginDetails');
     usernameController.text = userLoginDetails.username!;
   }
 
diff --git a/demo/app/lib/views/supported_credentials_list.dart b/demo/app/lib/views/supported_credentials_list.dart
index 4bf7620c..d3b528cd 100644
--- a/demo/app/lib/views/supported_credentials_list.dart
+++ b/demo/app/lib/views/supported_credentials_list.dart
@@ -51,7 +51,7 @@ class SupportedCredentialsListState extends State<SupportedCredentialsList> {
         children: <Widget>[
           const SizedBox(height: 20),
           const Text(
-            "Please select a credential type from below ",
+            'Please select a credential type from below ',
             style:
                 TextStyle(fontSize: 14, color: Color(0xff190C21), fontFamily: 'SF Pro', fontWeight: FontWeight.bold),
           ),
@@ -116,7 +116,7 @@ class SupportedCredentialsListState extends State<SupportedCredentialsList> {
                         navigateToAuthFlow(context, uri, widget.issuerURI);
                       },
                       child: const Text(
-                        "Request",
+                        'Request',
                         style: TextStyle(fontSize: 12, color: Color(0xff190C21)),
                       ),
                     ),
@@ -132,6 +132,6 @@ class SupportedCredentialsListState extends State<SupportedCredentialsList> {
 
   void navigateToAuthFlow(BuildContext context, Uri uri, String? issuerURI) async {
     Navigator.of(context)
-        .push(MaterialPageRoute(builder: (context) => HandleRedirectUri(uri, "wallet-initiated-flow", issuerURI)));
+        .push(MaterialPageRoute(builder: (context) => HandleRedirectUri(uri, 'wallet-initiated-flow', issuerURI)));
   }
 }
diff --git a/demo/app/lib/views/wallet_initiated_connect.dart b/demo/app/lib/views/wallet_initiated_connect.dart
index 383cd684..4b2f69cb 100644
--- a/demo/app/lib/views/wallet_initiated_connect.dart
+++ b/demo/app/lib/views/wallet_initiated_connect.dart
@@ -109,15 +109,15 @@ class ConnectIssuerListState extends State<ConnectIssuerList> {
                               var supportedCredentials =
                                   await connect(connectIssuerConfigList.elementAt(index).value.issuerURI);
                               var connectIssuerConfigValue = ConnectIssuerConfigValue(
-                                  issuerURI: "",
+                                  issuerURI: '',
                                   scopes: connectIssuerConfigList.elementAt(index).value.scopes,
                                   clientID: connectIssuerConfigList.elementAt(index).value.clientID,
                                   redirectURI: connectIssuerConfigList.elementAt(index).value.redirectURI,
                                   showIssuer: true,
-                                  description: "",
-                                  backgroundColor: "",
-                                  textColor: "",
-                                  logo: "");
+                                  description: '',
+                                  backgroundColor: '',
+                                  textColor: '',
+                                  logo: '');
                               _navigateToSupportedCredentialScreen(
                                   connectIssuerConfigList.elementAt(index).key,
                                   connectIssuerConfigList.elementAt(index).value.issuerURI,
diff --git a/demo/app/lib/wallet_sdk/wallet_sdk_js.dart b/demo/app/lib/wallet_sdk/wallet_sdk_js.dart
index 5c5edcbf..82f12592 100644
--- a/demo/app/lib/wallet_sdk/wallet_sdk_js.dart
+++ b/demo/app/lib/wallet_sdk/wallet_sdk_js.dart
@@ -260,7 +260,7 @@ class WalletSDK extends WalletPlatform {
       final result =
           await promiseToFuture(jsCreateOpenID4CIInteraction(initiateIssuanceURI)) as CreateOpenID4CIInteractionResult;
 
-      return {"pinRequired": result.userPINRequired};
+      return {'pinRequired': result.userPINRequired};
     } on PlatformException catch (error) {
       debugPrint(error.toString());
       rethrow;
@@ -297,7 +297,7 @@ class WalletSDK extends WalletPlatform {
       await promiseToFuture(jsVerifyCredentialsStatus(credential));
       return true;
     } catch (error) {
-      if (error.toString().contains("status verification failed: revoked")) {
+      if (error.toString().contains('status verification failed: revoked')) {
         return false;
       } else {
         debugPrint(error.toString());
@@ -378,7 +378,7 @@ class WalletSDK extends WalletPlatform {
 
   Future<Map<Object?, Object?>?> getVersionDetails() async {
     var versionDetailResp = await methodChannel.invokeMethod('getVersionDetails');
-    log("getVersionDetails in the app, $versionDetailResp");
+    log('getVersionDetails in the app, $versionDetailResp');
     return versionDetailResp;
   }
 
@@ -426,7 +426,7 @@ class WalletSDK extends WalletPlatform {
       localizedIssuerDisplays: localizedIssuerDisplays,
     )];
 
-    debugPrint("Issuer Metadata: $issuerMetadata");
+    debugPrint('Issuer Metadata: $issuerMetadata');
 
     return issuerMetadata;
   }
@@ -452,7 +452,7 @@ class WalletSDK extends WalletPlatform {
     try {
       final issuerID =
           await methodChannel.invokeMethod<String>('getIssuerID', <String, dynamic>{'vcCredentials': credentials});
-      log("get issuerID - , $issuerID");
+      log('get issuerID - , $issuerID');
       return issuerID;
     } on PlatformException catch (error) {
       if (error.code == errorCode) {
diff --git a/demo/app/lib/wallet_sdk/wallet_sdk_mobile.dart b/demo/app/lib/wallet_sdk/wallet_sdk_mobile.dart
index cb52d4f0..0e27c8bc 100644
--- a/demo/app/lib/wallet_sdk/wallet_sdk_mobile.dart
+++ b/demo/app/lib/wallet_sdk/wallet_sdk_mobile.dart
@@ -67,7 +67,7 @@ class WalletSDK extends WalletPlatform {
         'redirectURI': redirectURI,
         'issuerURI': issuerURI
       });
-      log("authorizationURL Wallet-Initiated-Flow -> $authorizationURL");
+      log('authorizationURL Wallet-Initiated-Flow -> $authorizationURL');
       return authorizationURL;
     } on PlatformException catch (error) {
       debugPrint(error.toString());
@@ -122,7 +122,7 @@ class WalletSDK extends WalletPlatform {
       });
       return credentialStatusVerifier!;
     } on PlatformException catch (error) {
-      if (error.toString().contains("status verification failed: revoked")) {
+      if (error.toString().contains('status verification failed: revoked')) {
         return false;
       } else {
         debugPrint(error.toString());
@@ -165,7 +165,7 @@ class WalletSDK extends WalletPlatform {
 
   Future<Map<Object?, Object?>?> getVersionDetails() async {
     var versionDetailResp = await methodChannel.invokeMethod('getVersionDetails');
-    log("getVersionDetails in the app, $versionDetailResp");
+    log('getVersionDetails in the app, $versionDetailResp');
     return versionDetailResp;
   }
 
diff --git a/demo/app/lib/wallet_sdk/wallet_sdk_model.dart b/demo/app/lib/wallet_sdk/wallet_sdk_model.dart
index d475419f..b82b36b1 100644
--- a/demo/app/lib/wallet_sdk/wallet_sdk_model.dart
+++ b/demo/app/lib/wallet_sdk/wallet_sdk_model.dart
@@ -1,4 +1,3 @@
-import 'dart:developer';
 
 class WellKnownDidConfig {
   final bool isValid;
@@ -355,13 +354,7 @@ class CredentialDisplayData {
 
   @override
   String toString() {
-    return 'CredentialDisplayData{' +
-        ' issuerName: $issuerName,' +
-        ' overviewName: $overviewName,' +
-        ' logo: $logo,' +
-        ' backgroundColor: $backgroundColor,' +
-        ' textColor: $textColor,' +
-        '}';
+    return 'CredentialDisplayData{ issuerName: $issuerName, overviewName: $overviewName, logo: $logo, backgroundColor: $backgroundColor, textColor: $textColor,}';
   }
 
   CredentialDisplayData copyWith({
@@ -440,13 +433,7 @@ class CredentialDisplayClaim {
 
   @override
   String toString() {
-    return 'CredentialDisplayClaim{' +
-        ' rawValue: $rawValue,' +
-        ' valueType: $valueType,' +
-        ' label: $label,' +
-        ' value: $value,' +
-        ' order: $order,' +
-        '}';
+    return 'CredentialDisplayClaim{ rawValue: $rawValue, valueType: $valueType, label: $label, value: $value, order: $order,}';
   }
 
   CredentialDisplayClaim copyWith({
@@ -517,12 +504,7 @@ class VerifierDisplayData {
 
   @override
   String toString() {
-    return 'VerifierDisplayData{' +
-        ' name: $name,' +
-        ' did: $did,' +
-        ' purpose: $purpose,' +
-        ' logoURI: $logoURI,' +
-        '}';
+    return 'VerifierDisplayData{ name: $name, did: $did, purpose: $purpose, logoURI: $logoURI,}';
   }
 
   VerifierDisplayData copyWith({
diff --git a/demo/app/lib/widgets/credential_metadata_card.dart b/demo/app/lib/widgets/credential_metadata_card.dart
index c636b0fb..a6eca6b2 100644
--- a/demo/app/lib/widgets/credential_metadata_card.dart
+++ b/demo/app/lib/widgets/credential_metadata_card.dart
@@ -1,4 +1,3 @@
-import 'dart:convert';
 import 'dart:developer';
 
 import 'package:app/wallet_sdk/wallet_sdk_model.dart';
@@ -39,7 +38,7 @@ class CredentialMetaDataCard extends StatefulWidget {
               (response) =>
           {
             setState(() {
-              log("status $response");
+              log('status $response');
               verifiedStatus = response;
             }
             )});
@@ -47,7 +46,7 @@ class CredentialMetaDataCard extends StatefulWidget {
     getIssuanceDate() {
       var claimsList = credentialClaimsData;
       for (var claims in claimsList) {
-        if (claims.label.contains("Issue Date")) {
+        if (claims.label.contains('Issue Date')) {
           var issueDate = claims.rawValue;
           return issueDate;
         }
@@ -60,7 +59,7 @@ class CredentialMetaDataCard extends StatefulWidget {
     getExpiryDate() {
       var claimsList = credentialClaimsData;
       for (var claims in claimsList) {
-        if (claims.label.contains("Expiry Date")) {
+        if (claims.label.contains('Expiry Date')) {
           var expiryDate = claims.rawValue;
           return expiryDate;
         }
diff --git a/demo/app/lib/widgets/credential_verified_information_view.dart b/demo/app/lib/widgets/credential_verified_information_view.dart
index a8f87e4b..0d7f4386 100644
--- a/demo/app/lib/widgets/credential_verified_information_view.dart
+++ b/demo/app/lib/widgets/credential_verified_information_view.dart
@@ -51,7 +51,7 @@ class CredentialVerifiedInformation extends StatefulWidget {
         controller: credDataController,
         shrinkWrap: true,
         itemBuilder: (context, position) {
-          if (credPrev[position].valueType != "image"){
+          if (credPrev[position].valueType != 'image'){
               return Row(
                 children: [
                   const Divider(
@@ -96,7 +96,7 @@ class CredentialVerifiedInformation extends StatefulWidget {
                             },
                           )
                         ],
-                      ) :  Column()
+                      ) :  const Column()
                     ),
                   ),
                 ],
@@ -145,10 +145,10 @@ class CredentialVerifiedInformation extends StatefulWidget {
         child: SingleChildScrollView(
           child: Column(
             children: <Widget>[
-              Row(
+              const Row(
                   crossAxisAlignment: CrossAxisAlignment.start,
-                  children: const <Widget>[
-                    Text( "Verified information", style: TextStyle(fontSize: 18, fontWeight: FontWeight.w700))
+                  children: <Widget>[
+                    Text( 'Verified information', style: TextStyle(fontSize: 18, fontWeight: FontWeight.w700))
                   ]
               ),
               const SizedBox(height: 10),
diff --git a/demo/app/lib/widgets/success_card.dart b/demo/app/lib/widgets/success_card.dart
index d98cfdec..57030eb5 100644
--- a/demo/app/lib/widgets/success_card.dart
+++ b/demo/app/lib/widgets/success_card.dart
@@ -9,6 +9,7 @@ class SuccessCard extends StatelessWidget {
 
   SuccessCard({required this.credentialData, this.verifierName, this.subTitle,  Key? key}) : super(key: key);
 
+  @override
   Widget build(BuildContext context) {
     return Scaffold(
         backgroundColor: const Color(0xffF4F1F5),
diff --git a/demo/app/pubspec.lock b/demo/app/pubspec.lock
index 5f07d9d1..8fbbfd52 100644
--- a/demo/app/pubspec.lock
+++ b/demo/app/pubspec.lock
@@ -167,10 +167,10 @@ packages:
     dependency: "direct dev"
     description:
       name: flutter_lints
-      sha256: "2118df84ef0c3ca93f96123a616ae8540879991b8b57af2f81b76a7ada49b2a4"
+      sha256: a25a15ebbdfc33ab1cd26c63a6ee519df92338a9c10f122adda92938253bef04
       url: "https://pub.dev"
     source: hosted
-    version: "2.0.2"
+    version: "2.0.3"
   flutter_secure_storage:
     dependency: "direct main"
     description:
diff --git a/demo/app/pubspec.yaml b/demo/app/pubspec.yaml
index 0bf59880..51a1883b 100644
--- a/demo/app/pubspec.yaml
+++ b/demo/app/pubspec.yaml
@@ -58,7 +58,7 @@ dev_dependencies:
   # activated in the `analysis_options.yaml` file located at the root of your
   # package. See that file for information about deactivating specific lint
   # rules and activating additional ones.
-  flutter_lints: ^2.0.0
+  flutter_lints: ^2.0.3
   flutter_launcher_icons: "^0.9.0"
 
 flutter_launcher_name: