What visual style did Chinatown Wars use as a first for the GTA series?

Grand Theft Auto: Chinatown Wars used cel-shaded polygons as a first for the GTA series.

The Nintendo DS version presents its characters, vehicles, and environments with polygonal models outlined in black. The result resembles a moving comic book, giving Chinatown Wars a distinctive visual identity while still preserving the series’ open-world crime-game format.

This approach suited the DS hardware and the game’s angled, rotatable camera. Rather than attempting the photorealistic look of Grand Theft Auto IV, Rockstar Leeds and Rockstar North emphasized bold shapes, readable silhouettes, and a stylized map of Liberty City. The game was released for Nintendo DS in March 2009.

The answer refers primarily to Chinatown Wars’ original DS presentation. Later versions were not identical: the PSP edition replaced much of the cel-shaded appearance with a more conventional look, and mobile releases were based on later adaptations. That platform difference can cause confusion, but the series-first visual style associated with Chinatown Wars is cel-shaded polygons with black outlines.