"A lot of big urban public transportation agencies have historically offered — at least since the Americans with Disabilities Act of 1990, but some before that — a kind of demand response for seniors, for the disabled, to connect to hospitals, et cetera," Henderson said. "It’s a part of the public transit service, but it was tricky because it had to be scheduled, and it's very expensive per rider."

Henderson said point-to-point service is necessary to serve groups like the disabled, the elderly and people in outlying areas with limited transportation access.

"SamTrans and these other public transit agencies have an obligation to provide wheelchair access and have drivers that know how to deal with seniors and can be respectful towards them and helpful," he said. "So, this kind of service is very important, and I'm just glad to see that it's staying within the public realm of the transit system, rather than punting it off."

Elliot Martin, research and development engineer at UC Berkeley's Transportation Sustainability Research Center, says these transportation programs are emerging because transit agencies have long struggled in areas with low ridership, but where service still has to be provided.

"This is a potential means for agencies to provide that kind of mobility potentially better, because technology now enables us to communicate our origins and our destinations better," said Martin. "It also may be a way for these agencies to deliver that service at a lower cost."

SamTrans is not the only Bay Area transportation agency to launch an on-demand transit option. The Santa Clara Valley Transportation Authority and AC Transit have also launched these services in recent years with varying degrees of success.

VTA’s on-demand FLEX service pilot program, which started and ended in 2016, didn't catch on.

"At the conclusion of the six-month pilot period, staff determined that ridership levels were not sufficient to extend the program in view of its high operating cost and low farebox recovery," said Holly Perez, a VTA spokeswoman.

However, AC Transit's Flex program has had success since its initial pilot in 2016. According to the transportation agency, that program was launched as an alternative to the elimination of service in areas of low ridership in the East Bay. It's enabled riders in Castro Valley and Newark to book trips from selected bus stops using a computer or smartphone. In March 2018, the board of directors voted to continue the Flex service beyond its initial pilot year.

“During the pilot year, over 700 unique customers tried Flex, completing 23,000 trips and returning 70 percent of the time after taking their first trip,” said AC Transit spokesman Robert Lyles.