ExEn is a brand new set of tools that allows developers to port their titles from XNA (Xbox New Architecture) to Microsoft WP7 and iOS. Essentially it provides an easy way for software companies to move their console games to mobile platforms.
With companies like Electronic Arts snatching up proficient iOS developers like Firemint to better compete in the mobile arena, a set of tools like this could really be a game changer.
This way, developers can design games in a familiar setting, and then easily move the game to mobile platforms...