Description taken from Nintendo DS version of this game

Thirty years after the original Space Invaders marched into video game history, an exclusive remake hopes to conquer both the PSP and Nintendo DS. While the goal once again is to eliminate all hostile Invaders in a series of fixed-screen shooting stages, new twists have been added to the familiar play mechanics. Boss battles, Invaders with distinct abilities, a techno soundtrack, and revamped visuals are but a few of the changes to the classic coin-op. The arcade-style atmosphere is heightened with score-enhancing bonus rounds, mini-games, and jackpot targets. Players can even challenge a nearby friend via wireless connection. ~ Scott Alan Marriott, All Game Guide