DETROIT -- More than 100,000 trips have been taken in robotaxis operated by Waymo in the U.S. Now, the self-driving car unit of Alphabet is expanding the service to iPhone users.
On the first anniversary of its pilot program in Chandler, Arizona, Waymo said it will begin offering an iOS app for its robotaxi service for iPhones.
The company also revealed new details of the service, which has been slow to offer fully autonomous cars without human "safety drivers" behind the wheel to take over in an emergency.
Waymo, which began a decade ago as Google's self-driving car project, said its service has 1,500 monthly users and has tripled the number of weekly rides since January.
Since late summer, Waymo has ramped up a "rider only" option without human safety drivers to a test group of a few hundred commuters.
While those people were not always charged initially, they are now paying rates that are competitive with Uber and Lyft ride-hailing services, according to a Waymo spokeswoman.
Most Waymo rides occur in the late afternoon and evening, with commuters using the service for everything from getting to work to having a "date night," Dan Chu, the company's chief product officer, wrote in a blog post.
The service is expanding and will add more riders who will join a waiting list by using the new iOS app. The service has been available on Android phones since the spring.
Despite this, John Krafcik, Waymo's CEO, told reporters in October he is unsure when commercial robotaxis will take off.
General Motors has delayed the rollout of its service and Ford's CEO has said the industry overestimated the arrival of self-driving cars.
"It's an extremely challenging thing to do," Krafcik told reporters at a dinner in Detroit. "I do share your sense of uncertainty, even in my role. I don't know precisely when everything is going to be ready, but I know I am supremely confident that it will be."