basically a DS that runs some other software as well sold in China.
From Wiki:
"The Nintendo DS is region free in the sense that any console will run a Nintendo DS game purchased anywhere in the world; it is the same system everywhere. However, the Chinese version games can only be played on the Chinese iQue DS, whose larger firmware chip contains the required Chinese character glyph images. Nintendo DSes from other regions cannot play the Chinese games, but the iQue DS can play games of other regions. Also, as with Game Boy games, some games that require both players to have a Nintendo DS Game Card for multiplayer play will not work together if the games are from different regions (e.g. a Japanese Nintendo DS game may not work with a North American Nintendo DS game, though some titles, such as Mario Kart DS, are mutually compatible). With the addition of the Nintendo Wi-Fi Connection, certain games can be played over the Internet with users of a different region game.
Some Wi-Fi enabled games (e.g. Mario Kart DS) allow the selection of opponents by region. The options are Continent and Worldwide, as well as two non-location-specific settings. This allows the player to limit competitors to only those opponents based in the same geographical area. This is generally determined through the internal region of the software (i.e. Japanese releases will automatically search for other users of the Japanese version, and so forth)."
