Arkham Asylum Lockdown, a combat-oriented basic version of the console and desktop game Arkham City for iOS devices (iPhone 3GS or later, iPod Touch 3rd generation or later, iPad and iPad 2), is now available in the US iTunes App Store after having been spotted in the New Zealand store earlier today. Players take the role of Batman fighting various nemesis who have escaped from Arkham Asylum with Infinity Blade-style graphics.