what's the difference between ACCESS_COARSE_LOCATION and ACCESS_FINE_LOCATION.

ACCESS_COARSE_LOCATION is network based location access meaning the location is by your network, it could work with buildings or underground trains as long as you have access to your network while ACCESS_FINE_LOCATION is using gps thus your phone needs to be united with the sky (Correct me if im wrong here).

Location updates in android

<manifest ... >
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    ...</manifest>

If you are using both NETWORK_PROVIDER and GPS_PROVIDER, then you need to request 

only the ACCESS_FINE_LOCATION permission, because it includes permission for both 

providers. (Permission for ACCESS_COARSE_LOCATION includes permission only for  

NETWORK_PROVIDER.)