From Bulbapedia, the community-driven Pokémon encyclopedia.
Ambrella is a video game development company that is also a subsidiary of Nintendo.
Ambrella first ventured into Pokémon with Hey You, Pikachu!, released for the Nintendo 64 in 1998. They followed this up with Pokémon Channel for Nintendo GameCube in 2003. They also released games for Nintendo DS, such as Pokémon Dash.
More recently, Ambrella developed My Pokémon Ranch and Pokémon Rumble, which were released on the Wii as WiiWare.