I helped the lovely people over at Open Planet Software design a soothing puzzle game for iOS
Get it on the iOS App Store
The best way to understand how to play this game is to just try it out for yourself. The second best way would be to think of it as sudoku meets snake, but that is already quite far-fetched..
Your goal is to get that grid radiating and in order for that to happen you need to channel the power (diamond-shaped tile) to the circular nodes sitting on the intersections. The number on the node indicates how many adjacent tiles need to be lit up exactly.
Not the patient puzzle-solving type? Don't fret! Gordon's ambient soundtrack will make sure you'll never step over that anger threshold.