Pokemon Producer Junichi Masuda has explained why the development team have opted to keep the series on the established Nintendo DS, rather than the newer Nintendo 3DS. Masuda says the reason is simple; it’s because of the humungous user base that the Nintendo DS has compared to the Nintendo 3DS.
So first, being a direct sequel to Pokémon Black version and Pokémon White version, we really wanted to make sure that players of the original game would be able to play the sequels. Maybe not all of them have a Nintendo 3DS, but they definitely had a Nintendo DS if they played the original games. Also, the Nintendo DS platform is really just owned by pretty much the most people around the world. So many kids and so many players from the around the world have the Nintendo DS platform, so it made sense that if we wanted to have the most people possible play the games to put it on the Nintendo DS. However, it wasn’t just about having Pokémon Black version and Pokémon White version players play the games. We wanted to make sure that it was enjoyable for new players, too. We also really wanted to focus on making sure the games could communicate with the original Pokémon Black and Pokémon White versions and it made the most sense to put the games on the Nintendo DS this time. However, we also wanted to have a nice surprise for the owners of the Nintendo 3DS so we developed the Pokémon Dream Radar application which is available on the Nintendo eShop. It’s kind of a supplementary game that features some action-packed gameplay where you can catch Pokémon using the gyro sensor and the AR function of the Nintendo 3DS. Since the Nintendo 3DS can play Nintendo DS games, if you have the Pokémon Black version 2 or Pokémon White version 2 in your Nintendo 3DS you can transfer the Pokémon you caught in Pokémon Dream Radar to your Nintendo DS game. We thought that was very interesting.