Superfall is a surprisingly enjoyable ragdoll physics game that combines tilt-controls along with numerous achievements and upgrade system that rewards you for continued play.
The core gameplay of Superfall involves a falling ragdoll that you control with left/right tilt. Along the way, you need to avoid obstacles to minimize damage while grabbing power-ups and avoiding getting stuck. The goal is to fall the furthest while staying in one piece.
Rotary wheels, pistons, grinders, blackholes, vents, traps, bumpers, and mines block your way during your descent. Special powers include "time warp" which slows down the action so you make a more planned descent, as well as the ability to shake your iPhone to wiggle your way out of a jam. Both can only be used a limited amount of time, so you need to conserve.
If that's all there was to the game, you'd still have a solid casual game, but the game also offers you a steady supply of 30 unlockable ragdolls that provide improved capabilities:
Earned in-game experience can be used to upgrade to the a better ragdoll, though some ragdolls can only be unlocked by accomplishing specific achievements. The early pacing seems really well thought out, giving you an incentive to play just a bit more to unlock the next achievement/ragdoll.
Check out the developer video:
Overall, SuperFall is a great combination of casual ragdoll gaming with an extensive achievement/upgrade system that may lure in both casual gamers and hardcore completionists.
App Store Link: SuperFall, $1.99