2. Brightness Manager Changing the brightness levels for apps each time you open them can get tedious. What if we tell you there is a way out? Brightness Manager can help you set specific brightness levels for each app on your phone. The application's UI is very minimal, and it is very easy to use. You just have to add the apps for which they want to set a different brightness level and then Brightness Manager handles everything else. This can be very helpful if a certain app does not support dark mode and you want to open that app in a very dim room without hurting your eyes. One thing that I like about this app is that you can set a default brightness level for when you exit a particular app so it jumps from one level to another instantly.