I've found the tracker much more reliable than previous versions. If I see something appear on it and keep heading in the same direction, I usually find it. The "travelling too fast" popup is getting annoying though, as I usually get it when I'm walking but leave the app to do something and come back after 30 seconds. Having to tap "I'm a passenger" when I'm not even in a vehicle is quite annoying. #firstworldproblems and all that.