Now, this is not for the faint of heart and does require some SIM cutting and hacking. That means we are not responsible for any damage you do to your SIM’s or iPhone. I’m not kidding, you have been warned!
With that said there are a couple of methods to have two phone numbers on your phone – the all AT&T (hacked and unhacked) method, and the mixed network method.
But before you start you need a dual SIM holder. There are a few out there. There are ones that switch phone numbers when you shut down the phone and ones that can get switched on the phone (We will talk about that later). These SIMs require no jailbreaking or hacking to use if you have two AT&T SIM’s. All you do is cut both AT&T SIMs with an knife to a template size then pop both sims into the SIM adaptor and anytime you want to switch lines you just shut your iPhone off and turn it on. Easy enough, right? But that is not the most ideal solution for people.
The method, which I think most people would prefer, requires a bit of jailbreaking and unlocking (with ziPhone) but it allows you to switch SIMs on the fly within the iPhone software (Yup, Apple does have dual SIM support in the OS).
I found a affordable auto switching dual SIM adaptor over at PhoneUnlockNow (They also sell the SIM cutter too for $20). Again you get both SIMs, cut them and put them in the dual SIM adaptor. Once that is done, stick the new hybrid SIM into your iPhone. With ziPhone you jailbreak, unlock and activate your iPhone.
Once that is done, on your iPhone navigate to the Settings icon then click on the Phone option. Under the Phone option if you scroll down to the bottom you will now see a new option called SIM Applications.
Under the SIM applications menu you can now select either SIM1 or SIM2 to be the SIM your iPhone uses to make and receive calls. Simple as that.
Now the dual SIM adaptor won’t automatically switch when you are getting a call, but if you have two phone numbers this is an easy way to carry one phone.
Again, this is not for the faint of heart and does require some SIM cutting and hacking. That means we are not responsible for any damage you do to your SIM’s or iPhone. Big thanks to Al for the step by step!