Has anybody noticed that the GPS on the Verizon iPhone seems to have a great deal of difficulty in maintaining a signal lock? I haven't tried Verizons Nav app, but with other pretty popular Apps such as Motion X GPS Drive or MapQuest Mobile the signal drops constantly making these apps virtually unusable (particularly Motion X's). The problems seems to be worse when your using Bluetooth audio in conjunction with the Nav app. It's extremely frustrating, being having Nav functions on your phone is so convenient.
There's been some chatter in regards to this on the Apple forums of which former ATT users are having GPS issues of which weren't present with their former GSM iphone 4. Issues include people who use 'hiking' or 'trail' apps and that their previous GPS generated 'path' on their old ATT iphone 4's would be straight, but with the Verizon iPhone they get a zig-zag line of which makes these apps also practically worthless. Run and Fitness apps which use the GPS to track how far they've traveled are also demonstrating issues.
I'm having the same problems with GPS apps on myVerizon iPhone 4. I've downloaded MotionX GPS Drive, MapQuest and Waze apps. They've all had great difficulty keeping a lock on a GPS signal. Sometimes they lose the GPS signal and never get it back -- after half an hour or so of waiting for the signal to return, I'll power the phone down and back up again, which seems to help for awhile.
I should note that I have the phone mounted on a vent holder on the upper center portion of my car's dashboard, with no case on it, so the antennas are fully exposed. The phone has a clear view of the sky, with no tall buildings nearby, no heavy tree cover or other obstructions. The GPS problems occur whether it's a short, 15 minute trip across town, or a 13 hour marathon drive. It's flakey and undependable, no matter what GPS app I'm using. I haven't tried the GPS apps that download an entire maps database to the phone (such as Tom Tom or Navigon) as I'm reluctant to spend that much money on an app that may not work properly. I finally took my first iPhone 4 back to an Apple store and explained the problem, whereupon they gave me another iPhone 4. Alas, the second phone has the same, highly erratic GPS behavior.
While searching around the Web, I've seen that AT&T iPhone 4 owners don't seem to experience these GPS problems. Has anyone here switched from an AT&T to a Verizon iPhone 4? Have you noticed any difference in GPS function?