The game features its own original plot, which leads into the story of Dead Space 2. It requires iOS 3.0 or later, and is rated 12+ for reasons that should be obvious to anyone who has played a game in the series. As added incentive, registering the game with EA unlocks content in Dead Space 2. It comes in at a fairly hefty 291 MB, so while waiting for the install you can check out a video of the game in action after the break.
This is supposed to be really really good. I have an iPad, It's tempting.