Lightly Night Mode

Lightly is a night mode / screen dimmer app for Android. It senses where in the world you are, and then automatically lowers the brightness of the screen based on when the sun rises and sets in your area. It has been proven in many studies that overexposure to bright light at night has a negative impact on your sleep. By lowering the brightness of your screen and converting bright blue light to warm orange light, a lot of those negative effects are removed, and you can sleep more easily at night.

GitHub: https://github.com/adrianblp/Lightly