Mario Kart DS was the first game to use Nintendo’s worldwide online matchmaking service, Nintendo Wi-Fi Connection, in 2005.
Nintendo released Mario Kart DS for the Nintendo DS in 2005. It retains the series’ item-based kart racing while adding dual-screen features, retro tracks, mission challenges, and online races over the handheld’s wireless connection.
Nintendo Wi-Fi Connection allowed compatible games to find opponents through Nintendo’s online service rather than requiring players to be in the same room. Mario Kart DS helped demonstrate how a handheld could support large-scale online competition.
The service later supported games such as Animal Crossing: Wild World and Pokémon titles. Nintendo Wi-Fi Connection should not be confused with the later Nintendo Network, which replaced it for newer hardware and games.