Basically I had a previous iPhone 4. The GPS on it was really accurate and always managed to pinpoint my location to within 5 metres. It was also extremely responsive and would update my position the moment I started moving. However it had a dot on the screen so I had it exchanged. On my new iPhone 4 the tracking is still accurate, but just not as good as before. It often shows me quite a bit further away than I really am. On top of that, my position will keep moving even when I'm standing perfectly still, whereas my previous iPhone 4 would just stay locked on to me completely. Furthermore it has a lag issue. Whenever I start moving, it takes about 10 - 15 seconds before it starts updating my position again. Whenever I stop, it takes awhile for it to realize that I have stopped moving as well, and my position on screen will fly further ahead than my actual position. After that it will slowly move back towards me and start jumping a bit again. Lastly, whenever my previous iPhone 4 managed to lock onto a GPS signal, it would pretty much almost have no blue-circle unless I zoomed in really close. However with my newer iPhone 4, it constantly appears and disappears again. Does anyone know why this is happening? Any solutions? Should I get it changed, again?