So an iPhone 5 from Verizon will work on ATT just no LTE. What about an iPhone 4S?
Thanks
The iPhone 4S is a different matter. At the time the 4S came out, Verizon wasn't actively trying to play nice with the government on net neutrality rules and spectrum issues. So they will only unlock the 4S for GSM carriers outside of the US.
Short answer: No, the 4S won't work on AT&T because Verizon treats the two phones differently.
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Yes, but VZW and Sprint are CDMA,
In this case that doesn't matter. While those networks are CDMA, the iPhone 5 that Sprint/Verizon are selling can technically operate on
both GSM and CDMA 3G networks. Sprint locks theirs for GSM, Verizon doesn't.
If you don't believe me, see for yourself:
https://www.macrumors.com/2012/09/21/verizon-iphone-5-confirmed-to-be-unlocked-on-gsm-3g-networks/
T-Mob is the only other GSM provider in the US, but it's 3G data is not compatible w/ ATT, only voice.
I don't mean to sound rude, but in this case, I don't think you really understand what you're talking about here.
T-Mobile's network is a GSM/HSPA+ network, just like AT&T. If you put an AT&T iPhone on a T-Mobile network, voice will work fine. Data will also work, but in some areas the 3G network operates on different frequencies than the iPhone is equipped to listen for. They're working to change that, though, and over about 95% of their network, T-Mobile 3G is already working fine on iPhones.
http://www.phonearena.com/news/T-Mo...MHz-spectrum-carrier-delayed-by-Sandy_id36196
Other than the spectrum issue, which T-Mobile is working to mitigate, the 3G technology they and AT&T use are exactly the same.