Use APKPure App
Get Overlay Battery Bar old version APK for Android
Show battery percentages by the white bar.
Show battery percentages by the white bar indicator.
You can check the remaining battery power level during full screen mode such as gaming.
This app is the utility app and also the sample application of my library "OverlayViewManager".
Source code
https://github.com/75py/Android-OverlayBatteryBar