I agree, that seems reasonable as outdoor transmission risk is negligible.I can't speak for @island but for me personally if that happened to me then I'd reduce my contact with other people to zero. Right now, for instance, I go to the supermarket once a week, a takeaway around once a week and the office several times a week and an outdoor walk several times per week. If I got a notification like that I'd cut out all of the above apart from the walk (which is outdoors and it's easy to be more than even 2m away so the chance of transmission is as close to zero as it's possibel to be). My judgement would be that stopping all of those activities other than walk is a perfectly sensible and appropriate response to being notified that I might have Covid-19. Banning leaving my home to even take outdoor exercise is madness. I appreciate the policing difficulties and why, therefore, the rules have ended up the way they are but that doesn't change my view that as an individual I would be abiding by the spirit of self-isolation if not the letter by acting in the above way.
Can someone confirm, if following the law to the letter, does it mean it's illegal to go out purely if the app tells you not to?