Hi I recently switched to T-mobile and I am extremely happy with the service(NYC)! However I am having problems with the phone getting a GPS lock. I have searched all over the net to see if others have had this issue but nothing really. First let me say that I got a replacement phone and that phone has the same issue and I have both in my possession. I can go out on my block and get a lock np but once I drive it says GPS signal lost on Google maps although I have full Cell signal and strong data. I tried using 4 different GPS fix apps and they get about 20 satellites in view in my APT but no lock on any of the 20. One time it did lock after about 1712 seconds lol. I tried the screw tightening suggestion but the screws where already solid. So I am trying to figure out what I can do is it something with Tmobile or the S4? Ironically I was on Sprint before with the same exact phone with horrid data and one or 2 bars and I would get a lock instantly every time. I hope I don't have to request a third phone! Thanks in advance for your help.