Plays very nicely. One comment is that it's not obvious that you can go through the rings in any order, so the first level where you might want to do this seem

Plays very nicely. One comment is that it's not obvious that you can go through the rings in any order, so the first level where you might want to do this seems extremely hard at first and is jarring compared to the previous couple of levels which were cakewalks. Maybe a little flashing info at the beginning of that level that tells you that you can go in any order at all. Also, the first two levels were just way too easy, maybe, and a little boring. It would be more fun if there were more reason to boost. A time bar at the bottom or top of the screen that starts full and ticks down to zero as an indication of how much bonus you will get when you finish would be a great indicator of where you are for time and I can totally see the user trying to boost at the end or throughout trying to finish the level while the time bar is at a more full state.