Grand Theft Auto: Liberty City Stories is a 2005 action-adventure game developed in a collaboration between Rockstar Leeds and Rockstar North, and published by Rockstar Games. The ninth installment in the Grand Theft Auto series, it was initially released as a PlayStation Portable exclusive in October 2005. A port for the PlayStation 2 was later released in June 2006. At the time of release, the recommended retail price of the PS2 port was around half the price of the PSP version, because the PS2 version does not feature the custom soundtrack ripping capability of the PSP version. Ports for iOS, Android and Fire OS devices were also released in December 2015, February 2016, and March 2016, respectively. The game is the first 3D title in the series to be released for handheld devices, and acts as a prequel to 2001's Grand Theft Auto III, using the same setting of Liberty City (a fictional parody of New York City). The single-player story, set in 1998, follows mobster Toni Cipriani, a character first introduced in Grand Theft Auto III, and his efforts to rise through the ranks of the Leone crime family, while slowly becoming involved in a power struggle among the city's various Mafia organisations. The PSP version of the game also includes a multiplayer mode through a wireless ad hoc network, which allows up to six players to engage in several different game modes. Liberty City Stories received generally positive reviews from critics, and was a commercial success, selling over 8 million copies as of March 2008 and becoming the best selling PSP game of all time. It was followed in October 2006 by Grand Theft Auto: Vice City Stories, a prequel to 2002's Grand Theft Auto: Vice City.