A pretty creative match-3 wherein the board isn't set to a grid or anything, and the physics of the bubbles becomes the challenge as you go on. Completing the game's entirely doable without ever dealing with that, but the three-star challenges on each stage vary* and are where most of the replay will come in (also turning a few simple stages into hair-pulling nightmares). I only just discovered there's an entire second "story" of stages off to the side, doubling what I thought was already a pretty solid game's length. Without the endless mode, or the zen mode, or...

I highly recommend it for anyone looking for a bit of variety.

* Each stage has three stars: "complete the stage", the second is usually "finish under X time", and the third varies, and might be "match three hearts" (usually a puzzle), "use under X bubbles" (worst thing, hands down), "destroy Y bubbles in a single drop", or others.