Correct me if I am wrong, but I am sure that as soon as you are found to be COV19 positive, you have to be quarantined until you get TWO consecutive negative results
If that is the case, the only people who should be out and about are people who have tested negative, so what use is it?
I am getting cynical in my old age and can only see this as a tracking device.
Also, the information is held by Amazon, and AFAIK, they have been known to sell personal information