Epic Games VP Mark Rein confirmed that the Unreal Development Kit, used to create the eye-popping App Store hit Infinity Blade, will be available to iPhone and iPad developers tomorrow, according to a report in The Wall Street Journal. UDK for iOS will allow iPhone, iPod Touch and iPad developers to create games using the same tech behind games including Gears of War, Mass Effect and dozens of other Unreal Engine-powered PC and console titles. "Apple's App Store is the most vibrant market for mobile gaming," said Epic co-founder Mark Rein. "If you’re going to make a game for a mobile device, and you want to make the most money, you’re nuts not to make it for iOS." Like standard UDK agreements on other platforms, developers can experiment with the engine or make free Unreal Engine-based games without incurring a licensing fee. Developers that want to sell UDK apps for iOS will have to pay a $99 licensing fee and 25 percent royalties after the first $5,000 in sales. Epic recently released its first iOS game, Infinity Blade, an action-RPG developed by subsidiary studio Chair Entertainment, creators of the Xbox 360 downloadable title Shadow Complex. Infinity Blade, featured on Apple TV advertisements, went on to top App Store sales charts following its release on December 9. Reports this week said numbers pulled from Apple's Game Center online game community service indicated $1.6 million in sales for the game's first four days. Rein said via his Twitter account actual sales of Infinity Blade -- which sells for $5.99 -- are even higher. Rein also told The Journal that Google's Android Marketplace has issues such as file size limitations and a hardware base that has numerous versions of phones, but added that he is confident Google is working towards resolving those issues.