Twinity is a 3D online virtual world. Initially developed by Metaversum GmbH, it is currently held by ExitReality. The game offers its population, called Twinizens, to navigate around virtual (historical) versions of real-world cities, also called a mirror world or a Metaverse. A public beta began in September 2008 with the release of the first virtual city, Berlin, which later was followed by Singapore, London, Miami and New York.