More than 4 million people in Australia have downloaded the COVIDSafe app, but the system granting health authorities access to the information it collects is not yet operational.
Prime Minister Scott Morrison has called the app a vital tool in protecting Australians against coronavirus.
But the ABC has confirmed that if a person tests positive to coronavirus today, the information on the app will be of no use to health authorities because the states and territories are yet to finalise how the data can be used.
"The rules on privacy are being finalised, along with final IT testing," a Department of Health spokesperson said.
"The system will be operational next week ahead of the decision on possible easing of restrictions."
Deputy chief medical officer Michael Kidd said that did not mean the app was useless while on Australians' phones.
"That facility is still to go live, that will be happening during the current week, but the important thing is that if people have downloaded the app and they have it running in the background on their phone, it's already gathering details of people you've been in close contact with," he said.
"There's a delay from now until when the contact tracer in the state or territory where you are based has activated the system."
Morrison pushes downloads
The app works by using Bluetooth technology to log when a person comes into close contact with others who have downloaded it.
If one of those people tests positive to Covid-19, the app is meant to help authorities identify those who have been in close contact with them.
The app can store 21 days' worth of contacts.
"Every Australian will be safer if those health officers are able to contact you more quickly if you have been exposed to the coronavirus and, importantly, that means that you will be less at risk of infecting others if they can get to you fast," Morrison said last month.
Yesterday he urged all Australians to download COVIDSafe, saying the sooner they did so, the sooner they would be able to go to the pub.
"It's like putting on sunscreen when you go out into the blazing sun. You can't go out in the blazing sun unless you've got that protection in place," he said.
Australia's national Cabinet has agreed to consider relaxing social distancing restrictions when it meets next Friday, but this will only occur if more Australians download COVIDSafe.
The federal government had previously said that 40 per cent of the population would have to sign up to the app for it to be effective, but now officials will not put a figure on it.
COVIDSafe is supported by all state and territory governments and also has the backing of key health groups such as the Australian Medical Association and the Australian Nursing and Midwifery Federation.