iphone can only be used on a GSM cellular network. This confines you to two options. AT&T or Tmobile.

When using these Unlocker Sims, they have to remain in the phone with your existing SIM from your carrier(att or tmo).

Also note that some phones in their settings have a "network" feature. This is usually defaulted to the Carrier it was made for. So if you had an ATT phone your network setting for it would be set to ATT. IF you are trying to unlock it so you can put your Tmo chip in, you would need to change the network setting manually and select from list of providers it sniffs...and select Tmo.

Some phones have this network setting set to a "auto" mode. It is supposed to auto sniff its stronger signal and go with it. But this might also play havoc and cause your phone to go into a roaming state. So i find it is better to manually change this auto network setting to be specific carrier you are trying to work with.

I work with both these carriers' devices in a lab and have found first hand that during our testing that the "auto" feature can be a little buggy. So we will force it to one or the other.

Just some thoughts. this might help those that are using the unlock sim and seeing random behavior.

fv<k the if0ne.

is this even legal, doesn't look like it will fit or work

iphone sucks anyways