diff --git a/CMakeLists.txt b/CMakeLists.txt
index dcb0dc0..639eede 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,10 @@
 #set(BUILD_INSTALL_DIR ${CMAKE_CURRENT_BINARY_DIR}/install CACHE STRING "install destination for 3rd party libs and plugins")
 set(BUILD_INSTALL_DIR ${CMAKE_CURRENT_BINARY_DIR}/install CACHE STRING "")
 set(WALLET_ROOT_DIR ${CMAKE_CURRENT_LIST_DIR} CACHE STRING "")
+if ((${CMAKE_BUILD_TYPE} MATCHES "Debug"))
+    SET(CMAKE_CXX_FLAGS_DEBUG "-O0 -g")
+    SET(CMAKE_C_FLAGS_DEBUG "-O0 -g")
+endif()
 
 include(cmake/solc.cmake)
 if(BUILD_XCOMPILE)
diff --git a/examples/wallet/app/main.c b/examples/wallet/app/main.c
index 7088895..a3dab6b 100644
--- a/examples/wallet/app/main.c
+++ b/examples/wallet/app/main.c
@@ -6,13 +6,13 @@
 
 /* system includes */
 #include <zephyr.h>
-#include <board.h>
 #include <device.h>
 #include <gpio.h>
 #include <string.h>
 
 /* local includes */
 #include "zephyr-wallet/wallet.h"
+#include "zephyr-wallet/shell_modules.h"
 
 #include "zephyr-wallet/lwm2m_client.h"
 /* 1000 msec = 1 sec */
@@ -54,11 +54,12 @@ void main(void)
 {
 	int cnt = 0;
     struct device *dev = init_led();
-    lwm2m_init();
+/*    lwm2m_init();*/
     privkey_t pk;
     memcpy(&pk.k, g_zephyr_private_key, 32);
 
     wallet_set_global_privkey(&pk);
+    wallet_register_shell_modules();
 
 	while (1) {
 		/* Set pin to HIGH/LOW every 1 second */
diff --git a/prj.conf b/prj.conf
index 2aeb91f..cbdf1e2 100644
--- a/prj.conf
+++ b/prj.conf
@@ -11,6 +11,7 @@ CONFIG_HTTP_PARSER_URL=y
 
 CONFIG_NETWORKING=y
 CONFIG_NET_TCP=y
+CONFIG_NET_UDP=y
 CONFIG_NET_IPV6=y
 CONFIG_NET_IPV4=y
 CONFIG_NET_CONFIG_SETTINGS=y
@@ -40,3 +41,5 @@ CONFIG_DHT_NAME="DHT11"
 CONFIG_DHT_GPIO_DEV_NAME="GPIO_1"
 CONFIG_DHT_GPIO_PIN_NUM=10
 CONFIG_SENSOR=y
+CONFIG_SNTP=y
+CONFIG_POSIX_API=y
diff --git a/prj_qemu_x86.conf b/prj_qemu_x86.conf
index 7da3a30..2f9e5a2 100644
--- a/prj_qemu_x86.conf
+++ b/prj_qemu_x86.conf
@@ -35,3 +35,5 @@ CONFIG_LWM2M_IPSO_SUPPORT=y
 CONFIG_LWM2M_IPSO_TEMP_SENSOR=y
 
 CONFIG_POSIX_API=y
+
+CONFIG_SNTP=y
diff --git a/zephyr-wallet/erc20_shell.c b/zephyr-wallet/erc20_shell.c
index e4c257b..49d2add 100644
--- a/zephyr-wallet/erc20_shell.c
+++ b/zephyr-wallet/erc20_shell.c
@@ -305,3 +305,6 @@ SHELL_CREATE_STATIC_SUBCMD_SET(sub_erc20) {
 	SHELL_SUBCMD_SET_END
 };
 SHELL_CMD_REGISTER(erc20, &sub_erc20, "erc20 utils", NULL);
+
+void erc20_shell_register()
+{}
diff --git a/zephyr-wallet/erc20_shell.h b/zephyr-wallet/erc20_shell.h
index 59342a2..f52c980 100644
--- a/zephyr-wallet/erc20_shell.h
+++ b/zephyr-wallet/erc20_shell.h
@@ -7,6 +7,7 @@
 #ifdef  __cplusplus
 extern "C" {
 #endif
+void erc20_shell_register();
 
 #ifdef __cplusplus
 }
diff --git a/zephyr-wallet/http_service.c b/zephyr-wallet/http_service.c
index a37da05..8037906 100644
--- a/zephyr-wallet/http_service.c
+++ b/zephyr-wallet/http_service.c
@@ -6,6 +6,7 @@
 */
 
 /* system includes */
+#define LOG_MODULE_NAME http_service
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wunused-parameter"
 #pragma GCC diagnostic ignored "-Wignored-qualifiers"
@@ -54,18 +55,15 @@ static int on_headers_complete(struct http_parser *parser)
 	if ((ctx->http.req.method == HTTP_HEAD ||
 	     ctx->http.req.method == HTTP_OPTIONS)
 	    && ctx->http.rsp.content_length > 0) {
-		NET_DBG("No body expected");
 		return 1;
 	}
 
 	if ((ctx->http.req.method == HTTP_PUT ||
 	     ctx->http.req.method == HTTP_POST)
 	    && ctx->http.rsp.content_length == 0) {
-		NET_DBG("No body expected");
 		return 1;
 	}
 
-	NET_DBG("Headers complete");
 
 	return 0;
 }
diff --git a/zephyr-wallet/sensor_service.c b/zephyr-wallet/sensor_service.c
index fb6b2ae..10edfca 100644
--- a/zephyr-wallet/sensor_service.c
+++ b/zephyr-wallet/sensor_service.c
@@ -80,3 +80,6 @@ SHELL_CREATE_STATIC_SUBCMD_SET(sub_sensor) {
 	SHELL_SUBCMD_SET_END
 };
 SHELL_CMD_REGISTER(sensor, &sub_sensor, "temperature sensor", NULL);
+
+void sensor_shell_register()
+{}
diff --git a/zephyr-wallet/sensor_service.h b/zephyr-wallet/sensor_service.h
index 3dbd126..74c2d70 100644
--- a/zephyr-wallet/sensor_service.h
+++ b/zephyr-wallet/sensor_service.h
@@ -1,6 +1,7 @@
 #ifndef _SENSOR_SERVICE_H_
 #define _SENSOR_SERVICE_H_
 /* system includes */
+#include <stdint.h>
 /* local includes */
 
 
@@ -8,6 +9,7 @@
 extern "C" {
 #endif
 
+void sensor_shell_register();
 int get_sensor_data(int32_t *temperature, int32_t *humidity);
 
 #ifdef __cplusplus
diff --git a/zephyr-wallet/shell_modules.c b/zephyr-wallet/shell_modules.c
new file mode 100644
index 0000000..58d0ecc
--- /dev/null
+++ b/zephyr-wallet/shell_modules.c
@@ -0,0 +1,25 @@
+/**
+* @brief 
+* @file shell_modules.c
+* @author J.H. 
+* @date 2018-11-29
+*/
+
+/* system includes */
+
+/* local includes */
+#include "shell_modules.h"
+#include "web3_shell.h"
+#include "sensor_service.h"
+#include "upload.h"
+#include "erc20_shell.h"
+#include "sntp_shell.h"
+
+void wallet_register_shell_modules()
+{
+    web3_shell_register();
+    sensor_shell_register();
+    upload_shell_register();
+    erc20_shell_register();
+    sntp_shell_register();
+}
diff --git a/zephyr-wallet/shell_modules.h b/zephyr-wallet/shell_modules.h
new file mode 100644
index 0000000..94a7410
--- /dev/null
+++ b/zephyr-wallet/shell_modules.h
@@ -0,0 +1,18 @@
+#ifndef _SHELL_MODULES_H_
+#define _SHELL_MODULES_H_
+/* system includes */
+/* local includes */
+
+
+#ifdef  __cplusplus
+extern "C" {
+#endif
+
+void wallet_register_shell_modules();
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _SHELL_MODULES_H_ */
+
diff --git a/zephyr-wallet/sntp_shell.c b/zephyr-wallet/sntp_shell.c
new file mode 100644
index 0000000..d26a44b
--- /dev/null
+++ b/zephyr-wallet/sntp_shell.c
@@ -0,0 +1,80 @@
+/**
+* @brief 
+* @file sntp_shell.c
+* @author J.H. 
+* @date 2018-11-29
+*/
+
+/* system includes */
+#define LOG_MODULE_NAME sntp_shell
+#include <net/sntp.h>
+#include <shell/shell.h>
+#include <posix/time.h>
+
+/* local includes */
+
+#define SNTP_PORT 123
+
+
+#include <misc/printk.h>
+void resp_callback(struct sntp_ctx *ctx,
+		   int status,
+		   u64_t epoch_time,
+		   void *user_data)
+{
+    struct timespec ts = {
+        .tv_sec = epoch_time,
+        .tv_nsec = 0
+    };
+    clock_settime(CLOCK_REALTIME, &ts);
+    struct k_sem *sync_sem = (struct k_sem *)user_data;
+    k_sem_give(sync_sem);
+}
+
+static int shell_sntp_sync(const struct shell *shell, size_t argc, char *argv[])
+{
+	struct sntp_ctx ctx;
+	int rv;
+    // semaphore to keep the app alive until the reply is received or timeouts
+    struct k_sem sync_sem;
+    k_sem_init(&sync_sem, 0, 1);
+
+	/* ipv4 */
+	rv = sntp_init(&ctx,
+		       CONFIG_NET_CONFIG_PEER_IPV4_ADDR,
+		       SNTP_PORT,
+		       K_FOREVER);
+	if (rv < 0) {
+		shell_error(shell, "Failed to init sntp ctx: %d\n", rv);
+		goto end;
+	}
+	rv = sntp_request(&ctx, K_FOREVER, resp_callback, &sync_sem);
+	if (rv < 0) {
+		shell_warn(shell, "Failed to send sntp request: %d\n", rv);
+		goto end;
+	}
+    k_sem_take(&sync_sem, K_FOREVER);
+end:
+	sntp_close(&ctx);
+    return 0;
+}
+
+static int shell_sntp_time(const struct shell *shell, size_t argc, char *argv[])
+{
+    ARG_UNUSED(argv);
+    ARG_UNUSED(argc);
+    struct timeval tv;
+    gettimeofday(&tv, NULL);
+    shell_print(shell, "%ld", tv.tv_sec);
+    return 0;
+}
+
+SHELL_CREATE_STATIC_SUBCMD_SET(sub_sntp) {
+    SHELL_CMD(sync, NULL, "sync", shell_sntp_sync),
+    SHELL_CMD(time, NULL, "time", shell_sntp_time),
+	SHELL_SUBCMD_SET_END
+};
+SHELL_CMD_REGISTER(sntp, &sub_sntp, "sntp utils", NULL);
+
+void sntp_shell_register()
+{}
diff --git a/zephyr-wallet/sntp_shell.h b/zephyr-wallet/sntp_shell.h
new file mode 100644
index 0000000..293fb63
--- /dev/null
+++ b/zephyr-wallet/sntp_shell.h
@@ -0,0 +1,17 @@
+#ifndef _SNTP_SHELL_H_
+#define _SNTP_SHELL_H_
+/* system includes */
+/* local includes */
+
+
+#ifdef  __cplusplus
+extern "C" {
+#endif
+void sntp_shell_register();
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _SNTP_SHELL_H_ */
+
diff --git a/zephyr-wallet/upload.c b/zephyr-wallet/upload.c
index 3d4a080..9772024 100644
--- a/zephyr-wallet/upload.c
+++ b/zephyr-wallet/upload.c
@@ -144,3 +144,5 @@ SHELL_CREATE_STATIC_SUBCMD_SET(sub_upload) {
 	SHELL_SUBCMD_SET_END
 };
 SHELL_CMD_REGISTER(upload, &sub_upload, "http upload service", NULL);
+
+void upload_shell_register() {}
diff --git a/zephyr-wallet/upload.h b/zephyr-wallet/upload.h
index 0018176..31933d0 100644
--- a/zephyr-wallet/upload.h
+++ b/zephyr-wallet/upload.h
@@ -7,6 +7,7 @@
 #ifdef  __cplusplus
 extern "C" {
 #endif
+void upload_shell_register();
 
 #ifdef __cplusplus
 }
diff --git a/zephyr-wallet/wallet.c b/zephyr-wallet/wallet.c
index 5ccd6e2..1968833 100644
--- a/zephyr-wallet/wallet.c
+++ b/zephyr-wallet/wallet.c
@@ -9,14 +9,14 @@
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wunused-parameter"
 #include <zephyr.h>
-#include <helpers/hextobin.h>
-#include <string.h>
-#include <stdlib.h>
 #include <shell/shell.h>
 #pragma GCC diagnostic pop
+#include <string.h>
+#include <stdlib.h>
 
 /* local includes */
 #include "wallet.h"
+#include "helpers/hextobin.h"
 #include "zephyr-wallet/utils.h"
 #include "zephyr-wallet/web3_rpc.h"
 
@@ -234,4 +234,3 @@ SHELL_CREATE_STATIC_SUBCMD_SET(sub_wallet) {
 	SHELL_SUBCMD_SET_END
 };
 SHELL_CMD_REGISTER(wallet, &sub_wallet, "crypto eth", NULL);
-
diff --git a/zephyr-wallet/web3_shell.c b/zephyr-wallet/web3_shell.c
index a07f8cd..1c22504 100644
--- a/zephyr-wallet/web3_shell.c
+++ b/zephyr-wallet/web3_shell.c
@@ -136,4 +136,6 @@ SHELL_CREATE_STATIC_SUBCMD_SET(sub_web3) {
     SHELL_CMD(eth_sendRawTransaction, NULL, "send a raw transaction", web3_shell_sendRawTransaction),
 	SHELL_SUBCMD_SET_END
 };
-SHELL_CMD_REGISTER(web3, &sub_web3, "http upload service", NULL);
+SHELL_CMD_REGISTER(web3, &sub_web3, "web3 utils", NULL);
+
+void web3_shell_register() {}
diff --git a/zephyr-wallet/web3_shell.h b/zephyr-wallet/web3_shell.h
index fde2f5c..ce4f9bf 100644
--- a/zephyr-wallet/web3_shell.h
+++ b/zephyr-wallet/web3_shell.h
@@ -7,6 +7,7 @@
 #ifdef  __cplusplus
 extern "C" {
 #endif
+void web3_shell_register();
 
 #ifdef __cplusplus
 }