iPhone game makes plumbing fun again.

Aqua Forest creatively combines a sketching program with physics. Players draw with water, stone, ice, and other objects in an effort to move an object to a goal. After placed, a line of water or any object becomes animated, cascading with gravity and iPhone movement. Even when the iPhone or iPod touch gets frequently overwhelmed by too much action on-screen—the frame-rate drips at about ten per-second—the unique game stays playful and engaging. But Aqua Forest only reveals glimpses of its brilliance, with its rules changing too frequently and the roster of objects with which you can paint overwhelming our palette.

Aqua Forest wins most often with its simplicity. Early levels just require you to rotate the iPhone to spill water over ledges into the goal. Quickly, stages introduce drawing and erasing, so you can make your own paths. When operating with only a few tools and the power to rotate the screen, the game perfectly matches the iPhone. We can’t imagine the finger swipes and tilting working on any other device.

But instead of giving dozens of challenges with just those variables, Aqua Forest keeps adding more tools. You can brush in hot rocks that turn the water into steam, choose from three kinds of slime-like liquids, suspend things from elastic ropes, build wood lines, and much more. Some challenges use only one or two of these, but we regularly forgot which icon did what when playing on free-for-all levels. And the worst areas ignore previously established rules—specifically the way you can rotate gravity—to nullify a potential solution.