I got a promo code for this and am enjoying it a lot. It's a cute polished puzzler with a three-star mechanic, and while that may sound somewhat boring at this point it feels really fresh. You are a mouse and the goal is to pick up three cheeses per level and make it to the exit. The mouse moves automatically and you can only jump vertically, that's the only control over your character you have. There are switches in some levels that change direction, and there are enemies/obstacles. You play the levels in casual mode first, and then you unlock puzzle mode where you can replay all the levels with limited jumps. For some levels that's quite hard so that really adds to the challenge. There are also leaderboards per world (you're scored by number of cheeses, time, and jumps) and lots of fun achievements.
Game works perfectly fine on my iPad 1. If you're in the mood for an action-puzzle game, definitely pick this up.