If you use a device like Samsung Galaxy Note versions you have the pen function enabled by default, and that drains a lot of battery from your device even if you are not using the pen.
Actually I never use the pen. If you are like me you can follow these steps and remove the pen in the settings to save you battery.
Go to Settings
For Galaxy Note devices go to System and then S Pen
Enable the battery saving option
Disable the Air view
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