This is a great one for Starcraft II fans. It's an App for the iPhone and the iPad that puts hot keys on the player's device for easier command over their units.
Players can see detailed stats and terrain information, they can check out the battle guide to see strengths and weaknesses of other units. Awesomely, it's going to be compatible with Apple's Retina display, meaning it will look sweet on an iPhone 4.
The bummer is that the client, which makes it possible to sync your device with your game, is Windows-only. Kind of strange given that a good portion iPhone and iPad owners probably own a Mac.
The App is due September 2010, but has no set release date. It will retail for $2.99.