A mobile game, or smartphone game, is a video game that is typically played on a mobile phone. The term also refers to all games that are played on any portable device, including from mobile phone (feature phone or smartphone), tablet, PDA to handheld game console, portable media player or graphing calculator, with and without network availability. The earliest known game on a mobile phone was a Tetris variant on the Hagenuk MT-2000 device from 1994. In 1997, Nokia launched Snake. Snake, which was pre-installed in most mobile devices manufactured by Nokia, has since become one of the most played games and is found on more than 350 million devices worldwide. Mobile devices became more computationally advanced allowing for downloading of games, though these were initially limited to phone carriers' own stores. Mobile gaming grew greatly with the development of app stores in 2008, such as the iOS App Store from Apple. As the first mobile content marketplace operated directly by a mobile platform holder, the App Store significantly changed the consumer behaviour and quickly broadened the market for mobile games, as almost every smartphone owner started to download mobile apps.