I wish I had invisible fingers.
It works like this: you're presented with an animated star field of sorts, packed with little randomly moving blips. When you touch a finger to the screen, the stars gather and explode from that spot. Drag your finger around and the stars follow.
Doesn't sound like much, does it? Wait. The blips change color. They change speed and direction depending on how you tap and drag. And when you add a second finger to the mix, you get an entirely different pattern of movement.
In fact, Gravitarium2 has 10 different animations, each launched by how many fingers you place on the screen at once. (That's some mighty impressive use of the iPad's multitouch capabilities.) You'll be amazed at how you get sucked into trying all the different combinations of tapping, dragging, and, well, multitouching.
What really elevates the experience is the new-age/classical soundtrack that plays while you're engaging with the screen. I highly recommend plugging in a pair of headphones while you do, because in my experience, a few minutes with Gravitarium2 can melt away stress like nothing else.
Indeed, while I'm loathe to use words like "psychedelic" and "hypnotic," because it's not the '60s and I'm not a hippie, it's hard to describe this app any other way. It's the perfect way to switch your brain off and just relax for a while.
If you tire of the standard animations, you can delve into the settings and modify just about everything: speed, color, opacity, tail length, and so on. There's even a two-player option--the app can pair you with friends or strangers via Game Center--though in my testing period I was never able to connect.
My only real complaint with Gravitarium2 is the opaque nature of fingers. Once you get more than four or five working the screen, it becomes hard to see what's happening beneath them. That's not the app's fault, but it does diminish the experience just a bit.
No matter. This app is well worth the $1.99 price of admission. Not convinced? Grab the free Lite version (which is limited to five touch points) and take it for a test-drive.