Note: Without root you need to manually grant Color Breeze the 'WRITE_SECURE_SETTINGS' permission with adb. If you need to know how to do this, go to: https://michaelschattgen.github.io/ColorBreeze

Color Breeze is an open source app which will automatically grayscale according to your schedule. Grayscaling your display will get your phone ready for bed. Stop yourself mindlessy checking your phone without receiving notifications. Users have found that they were less inclined to look at their screen when there were no popping colors. There is no fun in Instagram when everything is greyed out.

Added root support!

Google announced this feature as Wind Down which will be available on Android Pie (9.0), Color Breeze brings you the same experience to older Android versions, without having to root your device.