Android have well known dark mode and brightness level to decrease lighting on android screen. Unfortunately on android those setting not enough and need to be tweaked i divide this into 2 method Root and Non Rooted Mode Spoiler: Non Rooted Mode Explanation is pretty simple using any third party app that using accessibility services and overlay to change screen filtering 1. download, install and open redmoon 2. grant all required "Normal" Permission 3. change the profile as you like and enable it Spoiler: Rooted Mode Explanation is pretty simple this time you will use a third party app that will using root and KCAL (Kernel CALibration) to modify screen filters 1. download, install and open KCAL Night Light app 2. Grant SuperSU access and tweak the config 3. enable the services and done Spoiler: comparison Non Rooted Method: + wide compatibility + required no complicated setup and condition - overlay and services may affect battery and UI or screen appearance - need services to run in background affecting battery usage Rooted Method: + required no services or overlay + Save resource - very bad on compatibility - required kernel with supported KCAL setting self explanation: Non root method all this kind of apps will take advantage of overlay for make screen more darker below standard level meanwhile rooted mode just need KCAL (Kernel CALibration) to çhange screen filter to more darker. Non Rooted Method need services to prevent the app from being killed by system meanwhile Rooted Method not (KCAL setting)