Here's a thing, though... I got a notification this morning telling me I may have been in proximity to someone who may have Covid-19 ("may" doing a lot of work there).
I've been stationary in three places outside our house in the last week for more than 15 mins;
(1) my local pub for some lunch on Friday, where I was sat at a table, alone, and nobody else was within 2m of me (or even 5m)
(2) the cinema on Sunday; again, nobody apart from my youngest within 5m of us
(3) the bus going home from the cinema, nobody within 2m again
I've been in supermarkets a few times, but not been in the proximity of any given individual for more than 15 mins. Outside of that, everybody gets swerved. I'm probably more likely to get run over than anything else because I'm walking in the road to avoid people.
So... What is this app measuring?