If you already own the iOS version of XCOM: Enemy Unknown, be sure to update your games today as the multiplayer mode has been added to your game.
2K today announced that the latest update for XCOM®: Enemy Unknown iOS is now available, bringing added features such as iOS7 optimization, asynchronous multiplayer, and newly implemented leaderboards to iPhone, iPad and iPod touch*. After downloading the free update from the App Store, players can create their own custom multiplayer squad of aliens and XCOM troops and battle head-to-head asynchronously against friends and unknown foes around the world via Game Center.

Don't yet own the game? It can be yours from the Apple App Store for just $9.99 (USD) while it's on sale until October 13. After that date it returns to its normal price of $19.99.