A better idea could be, instead of using an app, to provide a personal device specific for this problem.
It should use NFC for tracing close contacts with others wearing it, display 3 of lights for three states:
Green: the person has not come in close contact with a suspect Covid19 patient, or she had it and now she tests negative.
Yellow: the person has maybe gotten in close contact with a Covid19 patient and has to test or is waiting a test result.
Red: the person is in quarantine cause she has tested positive to Covid19.
Those wearables might as well also monitor some vitals, should connect to a centralized server at least 3 times per day (for updates) or it will not go green but stay yellow for green codes (of course stay yellow for yellow codes and stay red for quarantined).
Perhaps it should also have a way to be associated to the wearer in case the police should check if the person is really wearing hers or what.
That’s it. You wanna get in close contact? Let’s check that out…
