One evening in February last year, a 23-year-old Uber driver named Niradi Srikanth was getting ready to start another shift, ferrying passengers around the south Indian city of Hyderabad. He pointed the phone at his face to take a selfie to verify his identity. The process usually worked seamlessly. But this time he was unable to log in. Srikanth suspected it was because he had recently shaved his head.

The Uber app prompted Srikanth to try again, so he waited a few minutes and took another picture. "I was worried about bookings. We have daily targets where if we complete a certain number of bookings, we get incentives," Srikanth says. "I was anxious to log in and start driving, and not waste any time." So he tried once more.