I've downloaded it. However before I did I read over the whitepaper about BlueTrace, aka the protocol which COVIDSafe is branched from.
Long story short, I am rather impressed at the solution which has been developed. It is very close to the sort of solution I or my team might have come up with had we been tasked with developing it, in-fact one of the idea's goes further than I would have done, so kudo's to the development team. This is a very well done job.
It balances the privacy of the individual, with the requirement to advice if close contact with a positive case is found. The data collected by the app and sent to the central server is highly limited in purpose, so should an agency such as the AFP attempt to gain access to the data under the guise of say an anti-terrorism law, they will be very disappointed. Furthermore, unlike some of the governments other half coughd approaches to data and data safety, IMHO this application is secure by design.
For the technically minded, the internal design of BlueTrace is available from here ->
https://bluetrace.io/static/bluetrace_whitepaper-938063656596c104632def383eb33b3c.pdf (Assuming that you haven't found it already). If people have questions and want me to translate from technospeak to plain English, you only need to ask. (I see the advantage of the entire population getting this app, so I'll do my bit).
(Getting data and metrics from point A to point B without person C seeing it at scale is kinda my day job, so I feel I am qualified to talk about this subject on a technical level)