Mass mobility services that facilitate simultaneous movement of several passengers by means of a bus or shared cabs, are becoming commonplace in several countries today. The main challenge faced by companies offering such services is the verification of claims regarding the boarding of passengers, made by either the passenger or the driver. Currently, such companies do not have a foolproof and yet usable solution to this problem and rely on manual verification of passengers during boarding. To this end, we propose a second factor of verification (2FV) and proof aggregation mechanism for establishing transparency and trust among the involved stakeholders. Specifically, we propose ProofRide, which exploits the time-domain similarities and inherent randomness in the observations about occurrences of motion-related events by the riders - the passengers and the driver. We discuss two scenarios-active and passive attempts of friendly frauds by the passengers and prove that ProofRide robustly verifies a trip with > 94% accuracy and scales across different types of vehicles including car, bus, bike, and metro trains.