CF.lumen is an add-on for Chainfire3D Pro. CF.lumen will change the colours of your Android device’s display based on the position of the sun. By default, your display will get a warmer tint (lower color temperature) when the sun is down, to look more like indoor lighting and less like the sun, which causes less strain on your eyes and doesn’t keep you awake as much. You can also customize your own colour filter and sleep time.