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Get Shades old version APK for Android
Shades takes screen brightness all the way to zero.
Shades allows you to lower your screen brightness beyond the system minimum. For devices with OLED displays, this can result in significant battery savings.
Be careful! If you set the brightness too low, don't tap OK. Simply use the back button to discard your changes.
If you do set the brightness too low, press your device's power button rapidly until the default brightness is restored.