I recently bought two 3Gs phones for my wife and I. Long story short, while trying to jailbreak my phone i messed up and inadvertently ended up with 3.1.3. So my question is, as I do not have any plans to jailbreak my wifes phone, can I switch sim cards between the phones as her phone still has the 3.1.2 firmware and then try to jailbreak that one?

Thanks.

Chris

You can, so long as both have done the initial activation and are functional as phones at present. First activation if bought from AT&T does associate SIM + iPhone S/N so it will complain if you try and do an initial activation with a different SIM than is registered at the time of purchase.

That said, be careful with your upgrade this time -- no way to back down from 3.1.3 on a 3GS without having your SHSH on file!

Thanks n1ckn4m3 for the response. Both phones were activated with AT&T and are currently working. I am going to try and hopefully it will work and I will not mess up the second time around. Thanks again.

As n1ckn4m3 mentioned, AT&T does not like card swap. They will most likely complain if you switch cards from phone to phone and may have you re-activate phones.
That's why I switched over to T-Mo. I pay $15 extra a month for everything unlimited. Worth it, right....

Thankfully they've eased off their IMEI + SIM stance that they had several years ago. At this point, the only check that I'm aware of is that if you purchase a phone from the AT&T store (not Apple store, I haven't done that, don't know if it's the same), when you take it home it wants to be connected to iTunes. If you put a different SIM in the phone and connect to iTunes, iTunes will refuse to activate, saying that the SIM in the phone is not the SIM required for activation.

That said, once you get past that part, you can switch SIMs around with little to no issue -- it's how I have a 3GS but am out of contract with AT&T right now .

Originally Posted by n1ckn4m3

Thankfully they've eased off their IMEI + SIM stance that they had several years ago. At this point, the only check that I'm aware of is that if you purchase a phone from the AT&T store (not Apple store, I haven't done that, don't know if it's the same), when you take it home it wants to be connected to iTunes. If you put a different SIM in the phone and connect to iTunes, iTunes will refuse to activate, saying that the SIM in the phone is not the SIM required for activation.

That said, once you get past that part, you can switch SIMs around with little to no issue -- it's how I have a 3GS but am out of contract with AT&T right now .

Yep. I've used my SIM (from my already activated iPhone) to activate another family members iPhone with no adverse issues.