diff --git a/app/build.gradle b/app/build.gradle
index b0c0d7b..33d3488 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -8,7 +8,7 @@ android {
     }
     defaultConfig {
         applicationId "com.uam.wmi.findmytutor"
-        minSdkVersion 22
+        minSdkVersion 23
         targetSdkVersion 27
         versionCode 5
         versionName "0.9.0-alpha"
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index aae98e5..c294244 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -15,6 +15,8 @@
     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
     <uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
     <uses-feature android:name="android.hardware.location.gps" />
+    <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
+
 
     <application
         android:icon="@mipmap/ic_launcher"
diff --git a/app/src/main/java/com/uam/wmi/findmytutor/activity/BaseActivity.java b/app/src/main/java/com/uam/wmi/findmytutor/activity/BaseActivity.java
index 1233fce..1e07dcc 100644
--- a/app/src/main/java/com/uam/wmi/findmytutor/activity/BaseActivity.java
+++ b/app/src/main/java/com/uam/wmi/findmytutor/activity/BaseActivity.java
@@ -4,11 +4,15 @@ import android.Manifest;
 import android.annotation.SuppressLint;
 import android.app.Fragment;
 import android.app.FragmentTransaction;
+import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.content.res.Configuration;
+import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
+import android.os.PowerManager;
+import android.provider.Settings;
 import android.support.annotation.NonNull;
 import android.support.design.widget.BottomNavigationView;
 import android.support.design.widget.NavigationView;
@@ -37,6 +41,7 @@ import com.uam.wmi.findmytutor.utils.RxSearchObservable;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.TimeUnit;
 
 import io.reactivex.android.schedulers.AndroidSchedulers;
@@ -54,7 +59,7 @@ public abstract class BaseActivity
     private final static int REQUEST_CODE_ASK_PERMISSIONS = 1;
     private static final String[] REQUIRED_SDK_PERMISSIONS = new String[]{
             Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION, Manifest.permission.ACCESS_LOCATION_EXTRA_COMMANDS,
-            Manifest.permission.WAKE_LOCK};
+            Manifest.permission.WAKE_LOCK, Manifest.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS};
     public DrawerLayout drawerLayout;
     protected BottomNavigationView navigationView;
     protected NavigationView drawerNavigationView;
@@ -204,7 +209,6 @@ public abstract class BaseActivity
 
     public void handleBackgroundTaskLifeCycle() {
         Boolean shouldServiceRun = PrefUtils.isEnableSharingLocalization(getApplicationContext());
-        Log.e("shouldRUN", String.valueOf(shouldServiceRun));
 
         if (shouldServiceRun) {
             startBackgroundLocalizationTask();
diff --git a/app/src/main/java/com/uam/wmi/findmytutor/service/BackgroundLocalizationService.java b/app/src/main/java/com/uam/wmi/findmytutor/service/BackgroundLocalizationService.java
index 21939f6..2df32d5 100644
--- a/app/src/main/java/com/uam/wmi/findmytutor/service/BackgroundLocalizationService.java
+++ b/app/src/main/java/com/uam/wmi/findmytutor/service/BackgroundLocalizationService.java
@@ -2,9 +2,6 @@ package com.uam.wmi.findmytutor.service;
 
 import android.Manifest;
 import android.annotation.SuppressLint;
-import android.app.Activity;
-import android.app.IntentService;
-import android.app.KeyguardManager;
 import android.app.Notification;
 import android.app.NotificationChannel;
 import android.app.NotificationManager;
@@ -21,13 +18,10 @@ import android.os.Bundle;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.IBinder;
-import android.os.PowerManager;
-import android.support.annotation.Nullable;
 import android.support.annotation.RequiresApi;
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.app.NotificationCompat;
 import android.util.Log;
-import android.widget.Toast;
 
 import com.google.android.gms.location.FusedLocationProviderClient;
 import com.google.android.gms.location.LocationServices;
@@ -44,8 +38,6 @@ import com.uam.wmi.findmytutor.utils.mapUtils;
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Timer;
-import java.util.TimerTask;
 
 import io.reactivex.android.schedulers.AndroidSchedulers;
 import io.reactivex.disposables.CompositeDisposable;
@@ -64,11 +56,12 @@ public class BackgroundLocalizationService extends Service {
     private static final String TAG = "MyLocationService";
     private static final int LOCATION_INTERVAL = 1000;
     private static final float LOCATION_DISTANCE = 5f;
+    public static String str_receiver = "background.location.broadcast";
+    public static Runnable runnable = null;
     private static long notify_interval = 10000;
+    public Handler handler = null;
     Location mLastLocation;
     Boolean stopService = false;
-    Intent intent;
-    public static String str_receiver = "background.location.broadcast";
     ArrayList<String> providers = new ArrayList<String>();
     LocationListener[] mLocationListeners;
 
@@ -78,12 +71,6 @@ public class BackgroundLocalizationService extends Service {
     private Runnable mStatusChecker;
     private FusedLocationProviderClient mFusedLocationClient;
 
-    PowerManager pm;
-    PowerManager.WakeLock wl;
-
-    public Handler handler = null;
-    public static Runnable runnable = null;
-
     public BackgroundLocalizationService() {
         providers.add(LocationManager.GPS_PROVIDER);
         providers.add(LocationManager.NETWORK_PROVIDER);
@@ -94,7 +81,6 @@ public class BackgroundLocalizationService extends Service {
                 new LocationListener(LocationManager.NETWORK_PROVIDER),
                 new LocationListener(LocationManager.PASSIVE_PROVIDER)
         };
-
     }
 
     @Override
@@ -103,24 +89,13 @@ public class BackgroundLocalizationService extends Service {
     }
 
 
-
     @SuppressLint({"MissingPermission", "InvalidWakeLockTag"})
     @Override
     public int onStartCommand(Intent intent, int flags, int startId) {
         Log.e(TAG, "onStartCommand");
         super.onStartCommand(intent, flags, startId);
-        try {
 
 
-            pm = (PowerManager) getApplicationContext().getSystemService(Context.POWER_SERVICE);
-            wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "MyWakeLock");
-            wl.acquire();
-            wl.release();
-
-        } catch (Exception ignored) {
-
-        }
-
         if (intent != null) {
             stopService = intent.getBooleanExtra("request_stop", false);
         }
@@ -138,10 +113,6 @@ public class BackgroundLocalizationService extends Service {
     @Override
     public void onCreate() {
 
-// when you done
-
-
-
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
             startMyOwnForeground();
         else {
@@ -186,9 +157,6 @@ public class BackgroundLocalizationService extends Service {
             handler.postDelayed(runnable, 15000);
 
         }
-
-
-
     }