A computer-implemented method is described for authenticating the identity of a caller. A mobile computing device receives, via a wireless communications network, an incoming call setup request initiated by a phone system of a caller, and executes an identity service application upon receipt of the incoming call setup request. The call includes a plurality of data packets. The mobile computing device extracts a caller identifier from the plurality of data packets. The caller identifier includes one or more bits at a first predetermined position within the plurality of data packets. The mobile computing device forwards the caller identifier to an identity service computing device. The identity service computing device determines an identity status of the caller. The mobile computing device receives, from the identity service computing device, an authentication token and the identity status of the caller. The mobile computing device displays the identity status of the caller.