Which Pokémon game was the first released for the Nintendo DS?

Pokémon Dash was the first Pokémon game released for the Nintendo DS. It launched in Japan on December 8, 2004, several months after the handheld system’s Japanese debut.

Developed by Ambrella and published by Nintendo, Pokémon Dash is a racing game rather than a traditional role-playing game. Players control Pikachu by drawing paths with the Nintendo DS stylus across the system’s touch screen. Courses feature different terrains, obstacles, and Pokémon-related challenges.

Pokémon Diamond and Pearl were the first main-series Pokémon role-playing games on Nintendo DS, but they arrived later, in 2006 in Japan. Pokémon Dash is therefore the correct answer when the question refers to the first Pokémon game on the hardware overall, not the first main-series entry.