BatteryStats

It is a simple battery check app.

It is safe because it does not require special privileges

BATTERY_PROPERTY_CURRENT_NOW

BATTERY_PROPERTY_CHARGE_COUNTER

BATTERY_PROPERTY_ENERGY_COUNTER

BATTERY_PROPERTY_CURRENT_AVERAGE

BATTERY_PROPERTY_CAPACITY

You can see the value.

(For more information https://developer.android.com/reference/android/os/BatteryManager.html)

※ In some terminal there is that the value will not be displayed correctly.