Switching iPhone between carriers

Workoutninja

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#1
Is it possible to take my current ATT 4S to Verizon? Anyone try it? I am starting a new job and they are on Verizon ... not sure if I want to use the phone they are providing.

Thanks
 

Europa

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#2
Is it possible to take my current ATT 4S to Verizon? Anyone try it? I am starting a new job and they are on Verizon ... not sure if I want to use the phone they are providing.

Thanks
No, an AT&T iPhone can't be used on Verizon.
 

rambo47

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#3
Neither Verizon nor Sprint will activate a phone on their networks that they did not sell themselves. Even if the technology is compatible it won't matter. Even if they sell the same model phone it won't matter. They did not sell THAT ONE in your hand, so they will not activate it.
 

Europa

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#4
Neither Verizon nor Sprint will activate a phone on their networks that they did not sell themselves. Even if the technology is compatible it won't matter. Even if they sell the same model phone it won't matter. They did not sell THAT ONE in your hand, so they will not activate it.
You're saying you can't buy a Sprint iPhone on Craigslist and then get Sprint to switch your number to it? I don't think that's true.

The reason that the OP's AT&T phone won't work on Verizon is that in addition to being locked to AT&T, it doesn't have an activated CDMA radio chipset, which would be required to access Verizon's network. It will only work as a GSM phone because only GSM is activated.
 

iP5

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#5
I'm sure he meant neither will connect an iPhone that didn't originate on their network but I see what you're saying.

Sent from Tapatalk
 

katelynneemma

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#6
You're saying you can't buy a Sprint iPhone on Craigslist and then get Sprint to switch your number to it? I don't think that's true.

The reason that the OP's AT&T phone won't work on Verizon is that in addition to being locked to AT&T, it doesn't have the right radio chip (CDMA) to access Verizon's network. It's a GSM phone.
the way I read that was Verizon will not activate a sprint phone even if it's the same phone and compatible? Not that they wouldn't activate a phone that wasn't purchased through them exactly.
 

Europa

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#7
I'm sure he meant neither will connect an iPhone that didn't originate on their network but I see what you're saying.
the way I read that was Verizon will not activate a sprint phone even if it's the same phone and compatible? Not that they wouldn't activate a phone that wasn't purchased through them exactly.
It was ambiguous so I just wanted to clarify it for the OP.
 

Vonwachtstain

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#9
Post on Craigslist you wish to trade for equivalent Verizon model. Most people prefer AT&T version so you should not have any problem trading.
 

rambo47

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#10
Yes, you can buy a Sprint iPhone on CraigsList and activate it on your own Sprint account. What you cannot do is buy a Verizon-branded iPhone and activate it on your Sprint account. The technology in the Sprint and Verizon iPhones is identical - it's the exact same iPhone - and it has all the right hardware to work. It's just that neither carrier will activate anybody else's device on their network.

My understanding is that with the iPhone 4s Apple standardized and they all contain both the GSM and CDMA radios. The AT&T iPhone 4s is identical to the Verizon iPhone 4s.
 

IllusionEntity

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#11
You're saying you can't buy a Sprint iPhone on Craigslist and then get Sprint to switch your number to it? I don't think that's true.

The reason that the OP's AT&T phone won't work on Verizon is that in addition to being locked to AT&T, it doesn't have the right radio chip (CDMA) to access Verizon's network. It's a GSM phone.
It's only the fact it's locked. The 4S is a universal phone. Hence the CDMA version having sim slots.
 

Apple iAddicted

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#12
I read the 4s is a World Phone it has both GSM and CDMA thats one reason I got the 4s cause it can run on both towers. My cousin got his iPhone unlocked by ATT but it is because he travels with his businesss and it needed a SIM from the country he was in to work properly. But Verizon and Sprint have to verify your ESN on their system for CDMA use and they usually won't do that especially when they sell iPhones now.


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Europa

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#13
It's only the fact it's locked. The 4S is a universal phone. Hence the CDMA version having sim slots.
Even the factory unlocked 4S iPhones won't work on CDMA networks. But I edited my post to clarify that it doesn't have an activated CDMA chipset. Only GSM is activated. The point is that it's not possible to get it running on Verizon's network. The AT&T 4S will only work as a GSM phone. The Verizon and Sprint 4S will work on CDMA and GSM. However, they cannot be used on AT&T.
 

Apple iAddicted

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#14
I edited my post to clarify that it doesn't have an activated CDMA chipset. Only GSM is activated. The point is that it's not possible to get it running on Verizon's network. The AT&T 4S will only work as a GSM phone. The Verizon and Sprint 4S will work on CDMA and GSM. However, they cannot be used on AT&T.
Why would ATT deactivate the CDMA chip. Ain't that there for maximum signal strength? Is there anyway way to reactivate it so you could roam on CDMA towers?


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Europa

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#15
Why would ATT deactivate the CDMA chip. Ain't that there for maximum signal strength? Is there anyway way to reactivate it so you could roam on CDMA towers?


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They didn't deactivate it. Illusion wanted to point out that it's there, but it's irrelevant and only leads to confusion because it doesn't work in the GSM models. It's just not activated because it's locked to AT&T and it's a GSM phone. No, you cannot use Verizon or Sprint on a GSM 4S. You cannot even use them if you buy a factory unlocked 4S at full cost (unsubsidized) for $649 - $849. It will work on any worldwide GSM network, but not CDMA networks. Most of the world is on GSM. This is why it's important that the CDMA 4S be capable of accessing GSM. The phone wouldn't be able to roam in most countries if it couldn't. There would just be no service.
 

Apple iAddicted

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#16
Ok....makes sense since CDMA devices have to taken to a store and hooked to their computer to be activated the first time, just thought that since CDMA can roam over to other CDMA towers maybe it was just a frequency switch for GSM to roam on them. And as I stated in my earlier post just cause it GSM your ATT phone don't work in every country My because been workin his own businesss for 4 years now and has to get his ATT phones unlocked to use SIMs in other countries where ATT has no service at all.


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Europa

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#17
Ok....makes sense since CDMA devices have to taken to a store and hooked to their computer to be activated the first time, just thought that since CDMA can roam over to other CDMA towers maybe it was just a frequency switch for GSM to roam on them. And as I stated in my earlier post just cause it GSM your ATT phone don't work in every country My because been workin his own businesss for 4 years now and has to get his ATT phones unlocked to use SIMs in other countries where ATT has no service at all.


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It would be nice if those of us with AT&T phones could roam on Verizon. They have better coverage than AT&T, especially in the west. If we don't have AT&T service, we have nothing. That was one nice thing about being on Sprint (years ago, before I had an iPhone). At least we could roam on Verizon.
 

Apple iAddicted

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#18
Yeah before I moved here I was with a mom/pop company called Cellular South now C*Spire they roamed off Verizon and Sprint when you left Mississippi, but where I moved had 0 service from any of their towers only ATT out here in the sticks and with the constant roaming after I moved outta MS they cut my contract and we got different prepaid phones until I found ATT go phone had best service so I went to the store and got on post pay. CDMA sucks here but in town and other places it better signal than ATT so go figure.....but this 4s has better signal strength than my wife's phone so the GSM antanna must be strong, we thought it was just switchin to CDMA towers but hey....learn somethin everyday lol


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bikerboy

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#19
I was told by a version customer care rep, that after 90 days from activating my 4s, I can call the globe department , unlock my 4s as it is a globe phone, so does this mean " if I wanted after unlocking the iPhone" I can use it on t-mobile or AT&T ?
 

Apple iAddicted

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#20
ATT is a GSM so sounds logical, not too familiar with Tmobile but with US carriers who knows, I have seen unlocked phones on eBay but those guys sometimes add CDMA carriers on their list and we already established they don't allow outside phones on their networks. You can use SIMs from from overseas carriers when your in their country that is what unlocking is really designed for. Maybe Europa can add some insite she seems to know a lot about US carriers


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