Mobile Adapter GB (Red, DDI Pocket PHS)

The Mobile Adapter GB was a short-lived peripheral developed by Nintendo that allowed the handheld Game Boy Color and Game Boy Advance consoles to connect to a mobile phone and utilize its cellular network. The accessory used a proprietary networking service called Mobile System GB operated by KDDI to exchange data. Following delays, the device and service launched in Japan on 27 January 2001. Together, they enabled online functionality for roughly 20 games, most notably Pokémon Crystal and Mobile Golf. Nintendo and Konami formed a joint venture, Mobile21, to create games that utilized the service.