What was the Mobile Adapter GB?

The Mobile Adapter GB, released in Japan on January 27, 2001, is a cable peripheral that connects a Game Boy Color, Game Boy Advance or Advance SP to a compatible Japanese mobile phone, putting the handheld online through the phone's connection. It was a Nintendo product built with Mobile21, a joint venture between Nintendo and Konami, and it launched at ¥5,800 (about $48 at the time), later cut to ¥3,800 (about $31 at the time) in July 2001.

Through it ran Mobile System GB, a paid online service whose server lived at gameboy.datacenter.ne.jp. Its flagship software was the Japanese Pokémon Crystal, with Pokémon Stadium Gold and Silver alongside, offering news, trading, battles and downloads years before handheld consoles had built-in wireless.

The market was not ready. Only about 80,000 adapters had sold by late March 2001, and Nintendo announced in May 2002 that the service would close, which it did on December 14, 2002, two years after it began.

The adapter never left Japan, and so an entire layer of Crystal, its online world, was removed from the Western releases feature by feature. The Mobile Adapter GB is the physical ancestor of every online Pokémon service since, and the least-known Nintendo peripheral of its era.