Uber made the concept of booking a cab with a phone call seem outdated. Now it’s trying to bring it back. The ride-hailing firm is testing out a new toll-free phone number in Arizona that people can call to book a car without needing a smartphone. Passengers can call 1-833-USE-UBER to reach an Uber contractor who will book a ride on the app and give them a price quote. Uber will then send driver details, expected arrival time and receipts via text message. Uber said the service is intended for people, especially the elderly, who may not own a smartphone and have access to its app. According to Pew Research, less than 20% of Americans don’t own a smartphone. “It was designed with older adults in mind, though our hope is anyone preferring conversational support will benefit from this pilot,” the company said in a statement on Thursday. “We built it based on feedback from older adults who told us the live conversations and simplicity of experience can make a difference for their transportation needs.” Uber cited Arizona’s growing elderly population as part of its strategy for rolling out the service to the state. (It previously conducted research for the program at community centers in Arizona.) Uber has used Arizona as a testing ground before, most notably for its self-driving car program. It could also prove useful in emerging markets where smartphone usage isn’t as widespread. Uber has already tested similar phone call-based services in Mexico, Ukraine, India and Egypt over the last two years, a company spokesperson told CNN Business. Customers can book various options, including Uber X, Uber Black and Uber Comfort, through the phone number, which the company stressed is not meant for general customer support. Uber plans to expand the calling service to other states in the coming months.