I picked up a nice little game called Break Liner, it's very simple with a nice aesthetic. And a gameplay mechanism that I haven't seen before. Kind of like a grown-up Doodlejump, just a single tap is all you do to play, it's all about timing. Very easy to start and stop playing when you have a minute or two.
Not sure if it's been mentioned yet, but Bit.TripRun is a pretty good platformer.