Air Assault is a simple arcade game where you have to destroy oncoming enemy troops, helicopters and more with your anti-air and mortar guns.
Each level is only one screen, with your defense on one side, and enemies approaching from the other. You have to divide your time between manning the anti air gun and mortar, as the former can't shoot ground enemies, and the latter is useless against air targets.
The gunfire and explosion sound effects are meaty, and the graphics are detailed without being too small for the iPhone's screen. Controls are simple and and work well. The odd part of Air Assault is that it has a very basic story and is actually set in Afghanistan, apparently during the current conflict. Some people might find this insensitive.
Air Assault is hooked up with OpenFeint, for competitive online global scoreboards, which does add an element of competition to it. From within Air Assault you can purchase and download extra missions, and there is one additional free scenario.
Air Assault is a fast paced, noisy and well made arcade game. It's very simple though, and it may only be the online competition that keeps you coming back to the pretty repetitious gameplay.