Nightsky is a meditative puzzle platformer with satisfying physics and brilliant level design, and its free right now on iOS. It's a game best played with a traditional pad and button set up, but its still a lot fun on your phone. The things that make it truly special -- the dream-like logic, the juxtaposition between the tense obstacle course gameplay and serene music and visuals, and the fun surprises that pop up every few minutes, all translate well enough regardless of what control scheme you elect to utilize.
If you have a phone that can run it, you should pick it up for the anti-price while you still can, and tell your friends while you're at it.
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