Starting from Android 8.1, when you set a wallpaper, the OS might change its colors based on it.
Sometimes what you get might not be what you'd wish to have.
This is why I've made this tiny app.
The app allows you to manually set which colors you'd like to request the OS to use.
This means that even if you have a relatively white background, you can still (if the OS allows it) have a dark themed notification drawer.
1. Ability to choose which photo to have as a background, and a color behind it.
2. Ability to have a double-tap-to-lock device.
3. Ability to choose which colors to request from the OS. Note that each color meaning depends on the OS alone.