Illusion Labs is probably best known for their first app, iPint, but have been making splashes since then with interesting apps that make great use of the iPhone's features and touchscreen. I tried out their Touchgrind app, and while it was a fascinating demo of how to combine an in-game physics system with the sensitive touchscreen controls, it was a little too tough for me to use (you have to really be a skateboarder, since the app really is a fingerboard, basically).
But Sway looks much more casual, and still puts the touchscreen and tilt abilities to great use. Like Rolando, it's a cartoony, physics-based platformer, but unlike Rolando, the mechanic here isn't rolling, but swinging. You swing the little characters around, and then use the touchscreen to grab onto various parts of the environment while exploring it.
Very intriguing. Like Touchgrind, the controls might be a little too sophisticated to appeal to all players (it looks tough coordinating which hand is which and exactly when to grab and let go), but we'll have to see how it works out -- if it starts out in an accessible way, Sway might be really impressive. Illusion Labs didn't tell us a price yet (their two other paid games are $5 and $7), but the game is set to hit the App Store soon.