diff --git a/gpsrelaysentinel/src/main/AndroidManifest.xml b/gpsrelaysentinel/src/main/AndroidManifest.xml
index 59a3bf0..2c92a4a 100644
--- a/gpsrelaysentinel/src/main/AndroidManifest.xml
+++ b/gpsrelaysentinel/src/main/AndroidManifest.xml
@@ -3,6 +3,9 @@
     xmlns:android="http://schemas.android.com/apk/res/android"
     package="cc.winboll.studio.gpsrelaysentinel">
 
+    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
+    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
+
     <application
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
@@ -32,6 +35,10 @@
 
         <activity android:name=".GlobalApplication$CrashActivity"/>
 
+        <service android:name=".MainService"
+            android:enabled="true"
+            android:exported="false" />
+
     </application>
 
 </manifest>
diff --git a/gpsrelaysentinel/src/main/java/cc/winboll/studio/gpsrelaysentinel/MainService.java b/gpsrelaysentinel/src/main/java/cc/winboll/studio/gpsrelaysentinel/MainService.java
new file mode 100644
index 0000000..1bad227
--- /dev/null
+++ b/gpsrelaysentinel/src/main/java/cc/winboll/studio/gpsrelaysentinel/MainService.java
@@ -0,0 +1,88 @@
+package cc.winboll.studio.gpsrelaysentinel;
+
+import android.app.Service;
+import android.content.Context;
+import android.content.Intent;
+import android.location.Location;
+import android.location.LocationListener;
+import android.location.LocationManager;
+import android.os.Bundle;
+import android.os.IBinder;
+import cc.winboll.studio.libappbase.LogUtils;
+
+public class MainService extends Service {
+
+    public static final String TAG = "MainService";
+    private LocationManager mLocationManager;
+    private LocationListener mLocationListener;
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        LogUtils.d(TAG, "Service onCreate");
+        initLocation();
+    }
+
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+        LogUtils.d(TAG, "Service onStartCommand");
+        return START_STICKY;
+    }
+
+    private void initLocation() {
+        mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
+        mLocationListener = new LocationListener() {
+            @Override
+            public void onLocationChanged(Location location) {
+                LogUtils.d(TAG, "Location changed: " + location.getLatitude() + ", " + location.getLongitude());
+            }
+
+            @Override
+            public void onStatusChanged(String provider, int status, Bundle extras) {
+                LogUtils.d(TAG, "Status changed: " + provider + ", status: " + status);
+            }
+
+            @Override
+            public void onProviderEnabled(String provider) {
+                LogUtils.d(TAG, "Provider enabled: " + provider);
+            }
+
+            @Override
+            public void onProviderDisabled(String provider) {
+                LogUtils.d(TAG, "Provider disabled: " + provider);
+            }
+        };
+
+        try {
+            if (mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
+                mLocationManager.requestLocationUpdates(
+                    LocationManager.GPS_PROVIDER,
+                    1000,
+                    1,
+                    mLocationListener
+                );
+                LogUtils.d(TAG, "GPS location updates requested");
+            }
+        } catch (SecurityException e) {
+            LogUtils.e(TAG, "Permission denied: " + e.getMessage());
+        }
+    }
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        return null;
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        if (mLocationManager != null && mLocationListener != null) {
+            try {
+                mLocationManager.removeUpdates(mLocationListener);
+            } catch (SecurityException e) {
+                LogUtils.e(TAG, "Permission denied when removing updates: " + e.getMessage());
+            }
+        }
+        LogUtils.d(TAG, "Service onDestroy");
+    }
+}