The virus tracking app had two million downloads in the 24 hours after it was launched on Sunday night but Dr Toija Cinque, a senior lecturer in communication, said there were major issues around privacy and system security.

She said certain apps, as well as those that "specifically offer measures to increase our individual and collective security were actually giving up privacy and creating new datasets to be exploited - often by unknown entities without our knowledge nor informed consent."

"Even when digital devices are switched off they are actually always on and collecting, curating and learning from the data we post online and even the data we do not," she said.

"While we know now that COVIDSafe data will remain in Australia, it is held by Amazon Web Services, in the United States meaning that they can be legally compelled to provide that data to law enforcement under the US CLOUD Act.

"Then there is the issue too of Bluetooth security. (The) COVIDSafe app uses Bluetooth to allow proximal devices to connect to each other over the air and lasting however long both devices are in use.

"Researchers have long underscored that the risks of Bluetooth security and potential rewards for malicious hackers are only growing."

Dr Cinque said her research had shown that young people who were very active online failed to take certain measures to protect their privacy.

"My recent study has found that young people are highly active on the internet and even though they have a clear understanding of what privacy means, few take actions to guard it," she said.

"Few took informed steps to ensure their online behaviours were thoughtfully shared or that their privacy settings were regularly maintained."

Dr Cinque said in some aspects Australians had been offered a deal to risk their privacy and online security to return to a somewhat normal life.

"In this case, many are showing that they are keen to trade-off concerns of what information is being gathered, who has access to it, for how long and what purposes with a return to 'normal' and being allowed to go outside more often and not least, improved mental health and potentially saving lives," she said.

"If the app works as expected for infection prevention and control... but there are concerns for individuals' privacy and system security.

"Moreover, the COVIDSafe app won't pick up asymptomatic carriers and it should not replace a policy of maintaining good hygiene, social distance (where and when possible) and wearing protective clothing in order to prevent infection.

"Indeed, coming in contact with a surface previously touched by someone with the virus hours earlier-a bus seat, café table, pedestrian traffic signal for example-might put people at risk."