No kidding, any Maps user can see their GPS location being collected when they use Maps. I think mynameisvlad may mean they wouldn't necessarily know if you stopped at a specific place as part of the location data collected when you're not using Maps, because in that case it may not use GPS. But I have a nice phone, battery life isn't really a concern to me, some software on the phone probably knows that too, and I don't trust the word of a random person on HN that the software wouldn't do an opportunistic GPS look up at least every now and then. In any case I want my phone to use GPS whenever it can so that it's as accurate as it can be, that's why I have in my settings GPS always enabled, with high accuracy (uses GPS, wi-fi, and mobile networks) and indeed I have Google Location Reporting on as well which looks up my location throughout the day whether or not I'm using Maps.