I just recently got an Iphone 6 and have noticed a very annoying and consistent problem. It often switches out LTE for 4G service. I've been able to isolate the problem and it seems to do it when I have less than 3 bars of LTE. I've never had this problem before on my Note 3, and my sister seems to be fine on AT&T with her Iphone 6. It's kind of annoying for reasons that T-mobiles 4g service is vastly slower than even 1 bar of LTE. Anyone knows what gives?