A pilot program of high-tech detection cameras is set to nab NSW drivers using their mobile phones.
In May, NSW became the first state to pass laws allowing red-light cameras to detect drivers using mobile phones.
Roads Minister Melinda Pavey launched the trial on Sunday that uses Australian-developed technology to be rolled out from January along the M4 Motorway and Anzac Parade.
Motorists photographed using their mobile phones while at the wheel will not, initially, be fined.
However, that may change provided the trial is successful.
"If at the end of the trial, the technology proves to be foolproof, the community will be made aware of its permanent use,” Mrs Pavey said.
An NRMA report released in November suggested illegal phone use behind the wheel was the number one safety fear for drivers.

NSW Roads Minister Melinda Pavey announcing a crackdown on drivers using mobile phones. (AAP) Source: AAP
Some 72 per cent of survey respondents nominated it as a fear, compared to 56 per cent who mentioned drink driving.
"I strongly believe this technology will change driver behaviour and save lives,” Mrs Pavey said.
A trial by the company behind the technology Acusensus, found that more than 11,000 drivers a day were being detected illegally using their phone.

The technology at work Source: Supplied
Acusensus managing director Alex Jannink told Fairfax he pursued the scheme after his friend was killed.
“Since my friend James was killed by an impaired and phone distracted driver five years ago, I have had a strong desire to develop this technology to save lives,” Mr Jannink said.
The Acusensus system uses both high-definition cameras and artificial intelligence to photograph drivers.