From the Home screen, drag down the Notification panel.
Tap the Settings icon.
Tap General.
Tap Battery.
Tap Battery usage.
From this screen, you can view details about how your battery power is being used.
Tap the Back icon.
Tap Power saving exclusions.
From this screen, you can manage which applications you exclude from Battery saver and battery optimizations.
Tap the Back icon.
Tap Battery saver.
Select a Battery saver setting.
Battery saver saves battery power by limiting access to certain apps. If necessary, tap TURN ON.
You've completed the steps!
