Originally Posted by gunnyman
Won't work. Vzw uses Cdma for voice and lte for data. Unless someone proves me wrong, the phone can't do voice calls on att network
It is possible to use a GSM carrier's sim in Verizon's phones for both voice and data. What would you like as Proof?
I don't have an X yet, but....
I have both Verizon and T-Mobile lines for work. (Verizon for personal).
My T-Mobile phone is a Galaxy S3. When T-Mo started supporting the iPhone, our corp rep swapped my sim to a T-Mo Nano SIM for me.
Since then, I have put my T-Mobile sim into my Verizon iPhone 5, VZW Galaxy S4, VZW BB Z10, VZW BB Q10, and VZW Nokia 928. Doing so works fine for voice, data and text messaging
on T-Mobiles network, but at EDGE speeds since these VZW phones don't support the 1700mhz UMTS/HSPA/HSPA+ bands that T-Mo uses. They do support the 1900mhz band that ATT uses, but I don't have an ATT sim handy to pop them in.
Oh, and I did need to use a SIM adapter to convert between nano and micro since only the iPhone 5 uses Nano sim. I do not recall results of trying to SMS, I really don't sms anyway.