The Watch Dogs ctOS companion app for iOS and Android will be available on the same day as launch, it has been confirmed.
The app will allow users to influence other player's games and set up races via two modes: Race and Free Ride. In the latter, a player using the app can use helicopters, road blocks and police pursuits to affect another user's race.
Custom races will also be available, with weather and checkpoints fully configurable. The free app boasts 26 challenges, including 13 Races and 13 Free Rides.
While the app cannot be tied to a user's console account, Ubisoft insists it is intentional.
"As you gain experience, you'll be able to improve your skills and enhance your options. For example, you'll be able to unlock four different police units; increase your ctOS powers to activate more hacks; or boost your helicopter by improving your pilot and sniper.
Watch Dogs releases May 27 for PS3, PS4, Xbox 360, Xbox One and PC.