Starts out as a very easy platform game, turns out to be very challenging and addictive. One of the best games in PSM.
There's an endless mode too which basically uses the textures of the stages and puts together a random endless course that becomes more and more difficult the further you go - pretty nice too. Also you can collect a set of awards, which are a nice extra thingy but honestly don' make much of a difference.
If you have a PS VITA, check PS Mobile, I think it is worth it. The stages look cool, the difficulty level offers something for everyone, and overall it's a nice game to play if you have some five minutes time waiting the train. I enjoyed it very much.