I am really enjoying this game. It's challenging without being impossible - and it's fun. Very unlike anything else I've played here so far. It's categorized with the puzzles, but it's really not puzzle-like. It is a bit like a marble popper and a bit like a match 3, but not exactly like either one. During game play, you shoot a colored ball at a whole bunch of colored balls that are "magnetized" to a rotating wheel in the middle of the screen and try to hit 3 of the same color together while your original ball is still "active" (the balls bounce also). As you go through the game, different elements are added to make it more challenging. There is no timer, but at a certain point, the balls become more jumbled and you have to try not to get too many balls on the wheel, or you will lose. Honestly, though, I have not really come close to losing a level. There are 10 stages (I believe) with 9 levels per stage. Plenty of game play.
If you're thinking of trying the game, I'd say it's well worth it. I purchased it for the deal of the day and I have definitely gotten my money's worth. It is probably worth a credit as well.
Cheers!