Droidsail Screen Filter is a custom screen dim control app. The default brightness control (in system setting) is using backlight only. But in this app, it can filter your whole screen with a custom r/g/b color and blend level besides backlight control, which could get more useful effect(e.g. more red/green/blue/dark. etc) for different purpose (for night, reading, match wallpaper, user style, etc). And this app is extremely easy to use, all control options are in one single float window. After first launch, a notification icon will appear on your top bar and you can adjust filter at any time. Also, this app provide a desktop widget to launch the filter control panel for convenience.Your can set/clear "Start on boot" to ask the app to run/stop after device rebooted. And if you want the app to fully exit (including close filter and remove the notification icon), just check "Fully exit mode" and click the top-right exit button. It’s easy, right? 🙂