While I personally wouldn’t install the app, I can see why from a scientific/medical perspective of why some may choose to install it.
One has to also acknowledge that its installation and use is a voluntary. Sometimes we get hung up thinking that such things affects everyone, but in this case, one make a choice whether it is in one’s interest to partake in the app.
If I were is a high risk category for complications, it may have merit knowing if one has been visiting ot being close to someone with COVID-19. This potentially would allow one with high risks to seek medical advice in relation to what one’s risks are and the likelihood of contracting the disease. If in the future there are some measures found that may alleviate the symptoms of the disease, it may allow early adoption of such measures which could reduce the severity of the disease symptoms.
Is one having severe complications or even dying worth the potential reduction in privacy while the virus is wild and a risk…any reasonable person would say yes. When one dies, privacy no longer becomes an issue for the deceased individual.
As @dropbear has indicated, there is mobile phone tracking in part in Australia and more broadly in other countries. This is an extension of what already exists. If one uses many location apps, location data is already collected and used potentially by those one is not aware.
