how can I tell if 4s IPhone is factory unlocked?

[petalino]

I am just about to buy a used "factory unlocked" 4s Iphone from a Craigslist seller.

Meeting him in one hour.

I need the phone to be factory unlocked, so that I can do OS upgrades without losing the unlock and I am going to signup for TMobile service for which the phone must be unlocked.

Is there a way that I can check if the phone is indeed factory unlocked and not Gevey or some third party service (which would cause OS upgrades to lock the phone) unlocked?

Thanks

 

[Jtludwig]

Put in a SIM card! It's not rocket science.

 

[petalino]

I get that, but if its not factory unlocked, would I be able to detect this?

So far I know, and I might be mistaken, a non factory unlock will be deleted when OS upgrade is installed.

I do not want this to happen.

Put in a SIM card! It's not rocket science.

 

[TouchArchive]

I am just about to buy a used "factory unlocked" 4s Iphone from a Craigslist seller.

Meeting him in one hour.

I need the phone to be factory unlocked, so that I can do OS upgrades without losing the unlock and I am going to signup for TMobile service for which the phone must be unlocked.

Is there a way that I can check if the phone is indeed factory unlocked and not Gevey or some third party service (which would cause OS upgrades to lock the phone) unlocked?

Thanks

Insert microSIM in iPhone and see the cellular network

 

[Jtludwig]

I get that, but if its not factory unlocked, would I be able to detect this?

So far I know, and I might be mistaken, a non factory unlock will be deleted when OS upgrade is installed.

I do not want this to happen.

Then just make sure it's not jailbroken (make sure there's no Cydia icon). That's the only other way to unlock them.

 

[cfedu]

Do a reset in front of the seller. If the seller agrees to wait it is unlocked or the seller is stupid and was also ripped off.