Passengers are allowed to leave their mobile devices on 'from gate to gate', says CASA spokesman Peter Gibson.

Qantas and Virgin customers will now be able to use their mobile phones on domestic and international flights.

Until now passengers had to turn phones and other mobile devices off because it was considered a safety risk.

Qantas and Virgin applied for approval from the Civil Aviation Safety Authority (CASA) to change that rule and it has been granted.

Other airlines are expected to follow suit.

CASA spokesman Peter Gibson said technological advancements had allowed for the changes.

"Aircraft are now designed and built with electromagnetic interference in mind," he said.

"So [passengers] can leave their devices, laptops, smartphones, tablets on from gate to gate.

"For big devices such as laptops you will need to stow them during take off and landing due to the risk of turbulence."

Qantas's head of engineering, Alan Milne, said the changes would take effect from this afternoon.

But he said once the aircraft doors were closed, the devices would need to be in flight mode.

"There's no network coverage up there anyway so there's no reason for having them on," he said.

"But it will enable [passengers] to write emails or text messages that will be sent when they switch back to normal mode after landing."

Virgin's head of customer service, Mark Hassell, said the change did not mean flyers needed to be worried about increased chatter on flights.

"Voice is a problem for people. People don't want passengers next to them talking throughout the flight. It's something that over the years has not proved to be popular where that is offered overseas," he said.

"But I think the ability to be able to send and receive emails, that is something there is a demand for and it is the area that we would pursue rather than voice."