A mobile game is a video game played on a feature phone, smartphones, smartwatches, PDA, tablet computer, portable media player or calculator. This does include games played on dedicated handheld video game systems such as Nintendo 3DS or PlayStation Vita. The first game on a mobile phone was a Tetris game on the Hagenuk MT-2000 device from 1994. Three years later Nokia launched the very successful Snake, starting in December 1997. Snake and its variants, that was preinstalled in all mobile devices manufactured by Nokia, has since become one of the most-played video games and is found on more than 350 million devices worldwide. A variant of the Snake game for the Nokia 6110, using the infrared port, was also the first two-player game for mobile phones. Now, mobile games are usually downloaded at app stores as well as via the mobile operator’s network, but in some cases are also embedded in the handheld devices by the OEM or by the mobile operator when purchased, via infrared connection, Bluetooth, memory card or side loaded onto the handset with a cable. The first downloadable content was introduced already in 2000. Many new WAP-enabled phones allowed new games to be downloaded. However, mobile games distributed by mobile operators remained a marginal form of gaming until the Apple App Store was launched in 2008. App Store, that was the first store operated directly by the mobile platform holder, significantly changed the consumer behaviour and quickly broadened the markets for mobile games, as almost every smartphone owner started to download mobile content. Mobile games are played using the technology present on the device itself or over the mobile cloud.