I have made a small game called Color Match Free. The point of the game is to match the color of a circle with the background color. However, the trick is that the color is altered only by tilting the phone. There is also some analytics of game performance with different colors and a training mode so you can freely practice and find out which color can be found in which position.
Feel free to give it a try and give any feedback, thanks!
Here is the link to the game: https://play.google.com/store/apps/details?id=turskagames.colormatch.free