Bedtime mode
In Android, there is a bedtime mode that can be automatically or manually activated. This mode essentially converts the screen color to grayscale, activates Do Not Disturb and can also restrict the user from accessing some apps if the user wants. The grayscale reduces visual stimulation, which helps relaxing; the other two features are self-explanatory.
Currently, there is an extension to turn the screen into grayscale and it's awesome.
Also, this mode can be useful to add in a future Digital Wellbeing panel of GNOME Settings.
Edited by Automeris naranja