New Android game Circ is an interesting little thing. You are a space ship that orbits planets. One touch of the screen boosts you away from one planet and onto the next, so players sort of “chain” their way up the scrolling screen, bouncing between gravity fields. It's playable with one finger. It's free, We've been enjoying it a lot. This is what it looks like:
You need Adobe Air on your phone to install it, plus a device with a bit of OOMPH to do it justice.
Eurodroid, NEW GAME: Circ