CF.lumen is a color-changing app for Android that changes the color of your screen based on the position of the sun or your custom configuration. It is intended for use in the evening, and you can use it to reduce eye strain and help you sleep better.

You can set the time of day (morning, afternoon, evening, or custom), and the app will automatically switch to the appropriate filter based on the current time.

It is very easy to use, with a simple interface and a helpful guide. You need to install it, set the time of day and the custom configuration, and you are done.

There is also an option to use the light sensor to automatically adjust the color, with a default setting of red, orange, yellow, and green.