Many iPhone users find it important to know how to unlock iPhone 4iOS 5 using UltrasnOw. Before you begin, you will need to make sure that the iPhone is already been jailbroken. You will also want to sync the iPhone and backup all the files on the computer, just in case you decide to restore later. Leave the iPhone tethered to the computer after you have synced it. Then tap on the Cydia icon and search for UltrasnOw 1.2.5. Once you find it, install it on the iPhone.
Now you will want to turn the power off and switch out the SIM card with the one from the carrier you desire to use the iPhone with. Now while the iPhone is still connected to the computer, turn it back on and wait for the iPhone to confirm that it is on the new network.
This is a very inexpensive and simple way to unlock the iPhone. It is possible to purchase a factory unlocked iPhone 4S or 4G. The trouble is that these are usually very expensive when purchased from the factory unlocked. It is easy and inexpensive to do the unlock yourself and you will enjoy the iPhone to its fullest.