Mobile Game Boy Adapter

The Mobile Game Boy Adapter (Japanese:  Mobile Adapter GB) is a peripheral for the Game Boy Color, Game Boy Advance, and Game Boy Advance SP which allows players to connect to compatible Japanese mobile phones. The peripheral was a collaboration between Nintendo and, a company that was jointly owned by Nintendo and.

It was first released on January 27, 2001 (originally planned for December 2000 ) with a recommended retail price of ¥5800, before a price cut to ¥3800 from July 19, 2001. By late March 2001, reported that Nintendo had only sold 80,000 units; the reason provided was that the only game to extensively use the Mobile Game Boy Adapter at the time was, which was targeted at a younger audience whom may not have access to a mobile phone.

Pokémon Mobile System GB
As a part of a service known as Mobile System GB (Japanese:  Mobile System GB), the Mobile Game Boy Adapter provided the hardware to compatible games, which used the network for wireless play across the nation via the now defunct , hosted by Nintendo Network Service Development. was the internet service provider of the Mobile System GB's network. The most well-known Mobile System GB is the Pokémon Mobile System GB used in the Japanese releases of and.

Despite its promises, the service was not much of a commercial success and closed down in December 14, 2002, probably due to the additional costs involved and the target audience of its biggest user (Pokémon Crystal) being off-limits. The closure of the Mobile System GB service makes it impossible for players to link to the server; however, it is still possible to link with friends provided that a network is used.

Package
The package was bundled with the original Mobile Game Boy Adapter itself, which was a blue cable that could be used to connect to compatible Japanese mobile phones. Included with the Mobile Game Boy Adapter is the "Mobile Trainer" cartridge, that only boots up when the Mobile Game Boy Adapter is connected to a compatible Japanese mobile phone. A special edition of the Mobile Game Boy Adapter came packaged with, which was a spin-off to the series used to test the Mobile Game Boy Adapter. After the Mobile Game Boy Adapter's release, different colored cables were sold separately which allows the player to connect to different types of phones, one of which was announced but never released.

Cables
In addition to the blue Mobile Game Boy Adapter cable, three other cables were announced, all of which were sold separately, apart from the green adapter, which was never released. They all allowed the player to connect to different types of phones.


 * Blue: the original cable packaged with the Mobile Game Boy Adapter. Supports connections to a digital cell phone terminal . The cable allowed for a maximum of 9600 bits per second (bps).
 * Yellow: this cable connects to a mobile phone, allowing for a maximum bit rate of 14.4 kilobits per second (kbps).
 * Red: this cable connects to a mobile phone, with a maximum bit rate of 36.6 kilobits per second (kbps).
 * Green: this cable would have support from Astel and, but it was ultimately never released.

Mobile Trainer
Mobile Trainer (Japanese:  Mobile Trainer) is a cartridge which came packaged with the Mobile Adapter GB itself, developed by MissingLink, the parent company of Denyusha. Prior to its release, it was previously given the tentative name of Mobile Starter Cartridge (Japanese:  Mobile Starter Cartridge). The cartridge served as a general guide to the Mobile System GB, which included a help menu about how to use the service and a glossary of key terms. Under a mobile settings menu, the player was able to alter their registration details, and confirm their remaining balance.

When the player boots up the cartridge, a connection screen checks whether the Mobile Game Boy Adapter is connected. The software will progress past the loading screen only once connected to a compatible Japanese mobile phone. The cartridge offered an system in which users could exchange text messages between each other. Another feature of the Mobile Trainer cartridge was access to the Mobile System GB homepage, which published featured articles around different compatible titles.

In the internal data of the Mobile Trainer ROM, graphics for such as (but not limited to),  and  have been found, as well as a test message about an alleged 'Pokémon game' which was never released known as Pokémon Moss (Japanese: ポケットモンスター苔). The purposes of these graphics are unknown.

(Hidden Pokémon content covered in below video at 28:48)

List of compatible software
Below is a list of all Game Boy Color and Game Boy Advance software which supported the Mobile System GB. Although five of these games (,, , , and ESPN Great Outdoor Games Bass 2002) were released outside of Japan, only the Japanese versions were compatible with the Mobile Adapter.

Similar devices
The Mobile Game Boy Adapter was not the first Game Boy peripheral offering play. From as early as March 6, 1998, 's GB Kiss Link Modem allowed players to access downloadable content from the Internet and send messages between friends, through a number of compatible games which had built-in ports, such as, the Japanese versions of  for the Game Boy Color, as well as the GB Kiss Minigames cartridge which came packaged with the GB Kiss Link Modem. The Link Modem was available through mail order.