Epic, the developer behind many smash hits such as Gears of War and the Unreal series, just managed to break another record earlier this week: its first iOS game Infinity Blade has become the fastest grossing iOS app ever, in a matter of days. The game, a 3D action-RPG where the goal is to destroy an overlord in order to free to free your people from his powers, is simply breathtaking, and is by far the most impressive game we’ve ever seen running on an iOS device, period. According to Epic V.P. and Co-Founder Mark Rein, Epic sold more than 300,000 copies of the game shortly after its launch, generating a whopping $2+ million in sales in less than a week. Since then, the game went on “cruise control”, as two weeks after its launch, Infinity Blade is still one of the top grossing apps in the App Store. To put things in perspective, Chillingo, the publisher behind Cut the Rope, “only” managed to generate $1 million within the first 10 days after the launch of the game. Beyond the impressive sales figures, Epic’s success again confirms the potential of the iOS eco-system, and shows how iPhone, iPod Touch and iPad became full blown gaming machines. Large game development shops such as Epic, Square-Enix, id software, and many others, are now shifting some of their focus to iOS-powered devices, at the expense of other well established gaming platforms, such as the Nintendo DS, or the Sony PSP.