GrabTaxi, one of the largest third-party taxi-booking apps here, is launching a mobile carpool service that it says will fill a gap between public transport and the more expensive taxis.

GrabHitch, which matches private-car drivers with commuters looking to go the same way, will cost half the price of a taxi ride for the same trip, the company said yesterday.

It announced its latest foray into yet another area of transport at a media briefing, adding that GrabHitch will complement its services in taxi-booking and private car-hire.

"With over half a million private cars in Singapore, there is a significant pool of vehicles with extra seats for more passengers," said GrabTaxi chief executive officer and co-founder Anthony Tan.

The service will be launched to consumers here by the end of the year. But potential GrabHitch drivers can sign up now.

Applications, which are subject to approval, require documentation such as credit card details, a driver's licence, vehicle registration details and insurance.

Checks will also be carried out to ensure that drivers have a clean driving record, said GrabTaxi co-founder Tan Hooi Ling.

She added that the driver's personal insurance would cover any accidents.

"But, of course, safety is important to us, so we have a 24/7 hotline passengers can call on," she said.

GrabHitch joins existing carpool services already on the market, including carpool sites such as ShareTransport.sg, Tripda, Executive Car Pool Club, SinJorean CarPool Group and Carpool.

The app will comply with existing car-pooling regulations, which state that drivers cannot offer more than two rides a day.

But they will be able to accept monetary compensation, which Ms Tan says will be distance-based, to "offset the cost of their journey".

Communications manager Christopher Sim, 26, says he is open to the carpool idea.

"It would really help to defray the cost of petrol and ERP (Electronic Road Pricing), which can be a bit pricey," he said.