MOTORISTS can now receive warnings about traffic delays or congestion on Adelaide roads through a mobile phone app developed by South Australian transport authorities.

The free AddInsight app broadcasts voice messages to drivers through a phone or a vehicle’s hands-free system about roadworks or other hazards ahead.

It uses real-time data from more than 400 Bluetooth sensors across the road network.

The app is unique in that it can respond to real-time changes in traffic conditions. Others only warn of pre-planned roadworks.

Transport Minister Stephen Mullighan said it was safe to use the app while on the road because it did not require input from a driver, could run in the background of other programs and used little battery power.

Mr Mullighan said the app was a world-first development and the State Government was in the early stages of working on opportunities to sell the technology to authorities in cities including Melbourne, Brisbane, Hobart, Canberra and Auckland, New Zealand.

It cost $20,000 to develop and is available for Apple and Android devices.

Each of the 400 Bluetooth sensors used cost about $1000.