The App Works Fine On Avd, But Not On Real Device

I really have very big problem with my project. When my phone is connected to the computer via USB cable, everything works fine, but when the phone is disconnected the app doesn't

Solution 1:

Most likely you have enabled the "Stay awake"-mode in the Developer options in the settings menu. When you disconnect the phone from the charger it will go into sleep mode after a few seconds.

The solution is to either use a partial wake-lock using the PowerManager or (in the above case) use a PendingIntent and the AlarmManager to trigger a event at a later time.