Bandai's Gundam Space Assault is a revelatory mobile shooter. Chock-full of deadly mechanized enemies, explosive power-ups, and gorgeous graphics, Gundam's gameplay will leave you gasping for breath--and your cell phone out of batteries.
There's as much going on during a pitched battle here as in most GBA games. Yes, the game slows down a tiny bit when asteroids are hurling at you, enemy infantry is flying in, the scariest boss in mobile gaming is firing full bore, and you call in your laser-blasting reinforcements. But it's a first-generation US Java game, and it's worth every penny you paid. Actually, much more.
Gundam Space Assault is my current favorite on the Sprint deck. It's tough, it's fast (play it with the power cord plugged in for best effect), and it's really fun. The only real problem here is that it may cause you to wear out the keys on your phone. Get Space Assault and look forward to the next Gundam--Atlantic Battle.