Covid test and trace ios App

It would seem to be the case, though I guess if you are indoors and don't want it on then it will pick up the next time. I've not tried this, but mine gave me no ill effects having it always and this morning gave me a cheery alert to tell me I'd not encountered anyone with a positive test in the last week. Of course it is annon, so its up to you to tell it your test was positive of course. Incidentally I had an antibody test last week. It came back negative, but the doctor pointed out that if I'd had it more than a couple of months ago there would be few to find in any case as the body then merely primes itself to make them again if required. Brian