Epic Citadel is a tech demo developed by Epic Games to demonstrate the Unreal Engine 3 running on Apple iOS, within Adobe Flash Player Stage3D and using HTML5 WebGL technologies. It was also released for Android on January 29, 2013. The application allows players to explore a medieval landscape without being able to interact with it otherwise. The application further has a built in benchmark mode and a "guided tour" mode. Nonetheless this demonstration garnered significant attention as it showcases a free SDK called Epic’s Unreal Development Kit (UDK)