Quiz Taxi is based on the German TV show of the same name. In the show passengers entering a perfectly harmless-looking taxi cab suddenly find themselves in a quiz show. The cab is rigged with cameras and the driver acts as the quiz master. The candidates have time to answer questions and win money until they reach their destination. After three wrong answers, however, the ride ends prematurely and they have to look for another cab. To make things a little easier two jokers are available. The candidates can either make a phone call or ask the driver to stop and ask a random pedestrian for help.
The Nintendo DS game works almost exactly like the TV show. There are different cities and routes to choose from. Completing all routes in a city will unlock the next city. This does not really influence the game, however, as the taxi travelling to its destination simply acts as a time limit for the quiz game. The quiz itself is a simple multiple choice dialog with three possible answers for each question. Just like in the TV show the player can use jokers to get answers to more difficult questions - and just like in real life these answers are not always correct. At random points the taxi may have to stop at a red light and this gives the player the chance to win back a joker by winning a mini game like Memory, Hot Wire or a spelling game.
There are also two wireless multiplayer modes. In "Team Mode" up to three player vote on a team answer and win or lose together. In "Combat Mode" up to three players ride separate taxis and try to win the most money within the time limit.