CF.lumen

If your device does not run Android KitKat or L (version 4.4 and higher), and you do not have root access, then you can stop reading here, as this application is not for you.

The developer of the popular SuperSU app has released CF.lumen for Android, a program similar to the desktop application f.lux. Research shows that cool colors are less straining on the eyes during the day, while warm colors are better at night. CF.lumen applies specific screen filters at the appropriate times, asking for your current location during the first launch to determine precise sunrise and sunset times. These filters include the ones mentioned above as well as specialized options, such as a night mode that displays only red to preserve night vision, a black-and-white filter, and a mode for color blindness, which, although experimental, has received exclusively positive feedback. The app offers a wide range of settings and features, including the ability to temporarily disable filters.