f.lux (preview, root-only) 22.0 [free]

f.lux removes the bright blue colors from your phone to help you wind down at night and returns your screen to normal the next day. This preview version is not a final
release. It requires a rooted phone, and otherwise it will not do much. We appreciate your help with bug reports and feature questions.
Most rooted Lollipop and Marshmallow devices (5.x and 6.x) will work.
Some rooted Kitkat (4.x) devices will work, but many do not.
Known issues:
- Many Samsung Galaxy devices do not work
- Your screen will flash anytime an app is updated through Google Play
Also, if you want to uninstall, do one of these things:
- Disable f.lux before uninstalling
- Reboot after uninstalling

• 01/20/2018: f.lux (preview, root-only) 22.0
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