The Neo Geo Pocket and Pocket Color were SNK's attempt to enter the handheld console market.
The Pocket was released in 1998, in Japan and Hong Kong. It didn't sell well, so it was replaced one year later by the Pocket Color. This had a wider release, including North America and Europe, and sold two million units. It was a good handheld, with a 16-bit CPU, 4096 colors, and 40 hours on two AA batteries for $70. It was cancelled in 2000 after SNK was bought by a pachinko company, though it lasted until 2001 in Japan.
The Pocket's claim to fame over the Game Boy line was the fact that instead of rubber pads, the D-pad used microswitches to sense directional movement. This difference allowed certain genres such as Fighting Games to be played effortlessly on such a small unit.