2K and Firaxis Games' iOS port of Xcom: Enemy Unknown is heading to iPad and other devices this Thursday (June 20). It'll be available from the App Store for £13.99 (here's a list of compatible devices - iPad 2, iPad 3, iPad 4, iPad mini, iPhone 4S, iPhone 5 and iPod touch 5th Generation).
Thanks to cloud functionality you'll be able to save your game online and play across multiple devices (if you have them). The game's head-to-head multiplayer mode won't be available at launch, but is promised as an update that will be added at a later date.