SYDNEY (BLOOMBERG) - The states of Queensland and Western Australia will ease coronavirus-related restrictions this week following signs of progress in the country's fight against the pandemic.

Queensland will ease stay-at-home restrictions from 11.59pm on May 1, the government said on Sunday (April 26) in a statement.

It will let people go for drives, have picnics, visit a national park and shop for non-essential items, as long as it's within 50km of home and social distancing is maintained. Outings will be limited to members of the same household or an individual and a friend.

Restrictions on other gatherings and visitors will remain in place. The Queensland government will monitor coronavirus cases and will review the easing after two weeks, State Premier and Minister for Trade Annastacia Palaszczuk said in the statement.

Western Australia will allow indoor and outdoor gatherings of up to 10 people from Monday, compared with the restriction of two persons introduced from March 30, the state's government said in a statement.

At the same time, all public playgrounds, skate parks and outdoor gyms will remain closed, while restaurants and food courts will continue to be limited to takeaways and home delivery.

The easing comes as Australia on Sunday launched a contact-tracing mobile app to boost its efforts to combat the coronavirus outbreak.

CovidSafe will record the digital handshake a mobile phone makes with other users of the app, according to a government statement. If someone catches the virus, they can then share that contact data with health authorities to speed up tracing.

"We need the CovidSafe app as part of the plan to save lives and save livelihoods," Prime Minister Scott Morrison said in the statement. "The more people who download this important public health app, the safer they and their family will be, the safer their community will be and the sooner we can safely lift restrictions and get back to business and do the things we love."

A broader testing regime and the contact-tracing app are seen as necessary for Australia to consider further relaxing restrictions on the overall economy.

The government has stressed the data will only be used by health officials and won't be accessible by police or other federal or state agencies.

SECURE INFORMATION

The app records the date and time, distance and duration of any contact. All information collected is securely encrypted and stored on the user's phone but no one, not even the user, can access it, Minister for Government Services Stuart Robert said in the statement.

"Unless and until a person is diagnosed with Covid-19, no contact information collected in the app is disclosed or able to be accessed," he said. "Once the person agrees and uploads the data, only the relevant state or territory public health officials will have access to information."

Officials will only be able to access information for a close contacts - when a person has come within approximately 1.5m of another app user for 15 minutes or more.

A new determination issued by the Minister for Health under the Biosecurity Act will ensure information provided voluntarily through CovidSafe will only be accessible for use by authorised state and territory health officials, according to the statement. Any other access or use will be a criminal offence.

An Australian Institute survey of about 1,000 people conducted last week showed 45 per cent of respondents were willing to use the app while 28 per cent said they wouldn't.