An Australian Government mobile application that you can use to lodge an Australian Electronic Travel Authority (ETA) application. The ETA allows eligible passport holders to travel to Australia for short term stays for tourism or business visitor purposes. See the Electronic Travel Authority website to find out more and check your eligibility to apply:
https://immi.homeaffairs.gov.au/visas/getting-a-visa/visa-listing/electronic-travel-authority-601

Australia has strict border measures in place to protect the health of the Australian community during the COVID-19 (Coronavirus) pandemic. You cannot come to Australia unless you are exempt from Australia’s travel restrictions and have a valid visa. Check the COVID-19 and the border travel restrictions website to determine your eligibility for an exemption:
https://covid19.homeaffairs.gov.au/travel-restrictions

Grant of an ETA through the app does not mean you have been considered for or granted an exemption to travel to Australia.

Please note that use of the Australian ETA app incurs a non-refundable service fee of $20.