Optus has extended availability for a traffic app that measured the congestion of roads by sampling the location of road users' handsets periodically as they drove.
The data service, which was launched last year, was yesterday opened up to consumers after previously being only available to organisations "such as road traffic authorities".
Optus piloted the system in late 2006 before launching the service for business and government organisations in June 2009.
The service used cellular floating vehicle data (CFVD) technology licensed from the local arm of British firm ITIS.
It was unclear how the system interfaced with Optus' backend systems. A technical spokesman was unavailable at the time of publication.
ITIS provided a brief explanation of CFVD on its website.
"By sampling the location of a mobile phone over a period of time, the route and velocity at which the phone is travelling can be determined," ITIS said.
"While an individual record of a mobile phone's position is typically less accurate than that of a corresponding GPS record, this is compensated for by the large number of mobile phones on any road, knowledge of the underlying road network and the application of statistical techniques."
Optus said that once CFVD data was collected from all 2G and 3G devices connected to its mobile network, "unique identifiers were removed and the data was aggregated on a road and time basis, to be interpreted and presented on maps."
"No individual user is identified in any traffic feed as this is removed at time of data collection and the observations are aggregated in timed road segment blocks," a spokesman said.
Optus re-assured consumers that the regular CFVD data transmissions needed to power the app would not identify them or interfere with their privacy rights.
The app worked for "major roads" in Sydney, Melbourne and Brisbane.
Called Travelview, it could be used on a pay-as-you-go basis for 55 cents for each SMS alert or via a $3.99 subscription, which offered users 1,000 alerts per month.