A gaming system configured to perform operations that include receiving, electronically, a first coded identifier, and providing, for presentation, on a display device of a mobile device, the first coded identifier for detection by a wagering game machine. The operations can further include detecting a second coded identifier presented by the wagering game machine after the detection by the wagering game machine of the first coded identifier. The second coded identifier is captured by an image capture device associated with the gaming system. The operations can further include transmitting, electronically, the second coded identifier.