Volvo tries out 'keyless car' app in Sweden
The car manufacturer Volvo is to try out a phone app in Sweden which the firm claims could replace the car key.
The Bluetooth app can control door locks and start or stop the engine, but the firm told the BBC that additional security measures would also be used inside the vehicles.
The app will also let car owners share "digital keys" with others and download keys before renting vehicles.
If the trial is a success the app could be launched next year.
Volvo will continue to offer physical keys to customers who want them, the firm said.
The trial will be in partnership with a fleet of hire cars at Gothenburg airport in Sweden.
Keys with batteries
Potential problems such as mislaid phones and handset battery life are already a factor of modern life, Martin Rosenqvist, director of new tech and services at Volvo, told the BBC.
"If you lose your car key you need to go to a Volvo dealer - if you lose your phone you have to get a new phone. You can acquire a new app on a new phone," he said.
Mr Rosenqvist pointed out that other essential travel items, such as mobile boarding passes for flights, already require battery life to be factored in for the duration of travel.
"Our app has marginal effect on battery life," he said.
The app communicates with "a Bluetooth installation" inside the car, Mr Rosenqvist said, but acknowledged that extra security would be required.
"It is a digital key but there is also a digital lock and they need to communicate with each other in the right sequence," he said.
"Just listening to the phone is not enough," he added, although he declined to comment on what the additional steps would be.
A cybersecurity expert, Professor Alan Woodward, warned however that Bluetooth was "a security conundrum" because the technology was originally designed as a short-range, replacement for cables.
"The security is defined in the standards so as to allow for 'flexibility'," he explained.
"However, this flexibility has a downside in that the developers have to pay attention or they can leave it open to eavesdropping or hijacking.
"It is not difficult to mitigate against the various forms of attack [but] you need to developers to be aware of the threat in order to ensure the mitigation is in place," he added.