The SA Government has launched a six-month trial of an on-demand bus service.

Residents in Mount Barker and the Barossa have become the first to access the service, which is aimed at getting more people to use public transport.

Nine buses across both locations can be hailed by a mobile phone app called Keoride.

The Mount Baker service costs $1.50 for adults and $1 for concessions, including seniors, per trip.

In the Barossa, adults will have to pay $6 and concession, $3.

The $1.7 million trial is part of the Marshall Government's bid to improve public transport services.

“This is an innovative new approach to public transport, we said when we came to government that we wanted to review how public transport was delivered in South Australia and that is exactly what we have been able to do,” Acting Minister for Transport and Infrastructure David Spiers says.

“Millions of people use ridesharing apps across the country so they should be very familiar with this technology which should make it easy for them to adapt to quickly.

“Like ridesharing, passengers will be able to track where their bus is and order it to a point near their location to save them waiting in the rain or heat.”

He says the same services may be accessible in Adelaide suburbs in the future.

“I think once we work through if the trial is succeeding, we will look to metropolitan options for this. I think the outer suburbs in particular would lend themselves to this,” Mr Spiers said.

“One of the things we want to look through as part of this trial is how cost effective it is. We want to provide a superior public transport service in South Australia.”

Keoride already operates between Narrabeen and Mona Vale on the Northern Beaches of NSW, as well as around locations in Macquarie Park.