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Get [ROOT] PanelOff — Disable Back old version APK for Android
The world's smallest backlight disabler for Android at just 77 KiB.
This app serves one purpose: disable the LCD or OLED backlight on Android devices using root.
You MUST be rooted for this solution to work.
To enable the backlight again, lock and then unlock the device.
https://github.com/tytydraco/PanelOff