It is the first game in the series to be specifically built from the ground up for the Nintendo DS, since the previous titles were remakes of Game Boy Advance games. It was released in Japan in April 2007, and North America and Europe in 2008. Character and promotional art was drawn by Tatsurou Iwamoto.
The game, which takes place seven years after the third game, features a new protagonist called Apollo Justice who takes over after Phoenix Wright (who appear as a major supporting character) and features a new gameplay gimmick; the bracelet, which has the ability to "zoom in on witnesses to gather information regarding them". This is denoted as the perceive function in the game, the bracelet is used in court to spot actions made by the witness that show nervousness. Apollo Justice shouts "Gotcha!" once the player spots such an action.
- Apollo Justice
- Trucy Wright
- Phoenix Wright
- Klavier Gavin
- Kristoph Gavin
- Ema Skye
- The judge
- Machi Tobaye - a teenaged pianist accused of murder.
Episode 1: Turnabout Trump - Apollo's first case involves him defending Phoenix Wright in the murder of Shadi Smith.
Episode 2: Turnabout Corner - Apollo defends a member of the Kitaki family, a family of feared gangsters in the city.
Episode 3: Turnabout Serenade - Apollo has to defend a teenage pianist in the murder of a singer's manager.
Episode 4: Turnabout Succession - This episode introduces the Jurist System, in which the verdict is decided by the consensus of six average citizens.