iPhone UNLOCK

If you want to unlock your iPhone, there are a few ways to go about doing so. If you've been faithful to your contract, you may be able to do so via your carrier network or through a network-authorized service. However, if you can't unlock through your carrier, you can unlock using a third-party program. 
Third-party unlockers covered in this article are:

• Ultrasn0w unlock from Cydia: Ultrasn0w has been around as long as iPhones have existed but is limited to jailbroken iPhones and compatible basebands up to iPhone 4.
• Gevey SIM unlock: A hardware exploit that relies on specialized SIM tray interposer. You do not have to jailbreak your iPhone to use this.
• R SIM interposer: An alternative to Gevey SIM and also not limited to jailbroken phones.
• iPhone IMEI number: This is the best unlock procedure for any iPhone model, baseband or iOS. Any service that offers iPhone unlock using an IMEI number provides a permanent or factory unlock.
• SAM ticket: Reliant on tickets that have been saved when using SAM unlock.

The easiest way to unlock a phone will always be through your carrier or a service they authorize. Look up your carrier on Apple's support site and see which carriers have unlocking services. Assuming you paid for your phone in full, the network should help get your iPhone unlocked for free or a small fee.

Finding Your iPhone's Baseband

Whether or not an unlocker can unlock your phone relies in part on what your phone's model and baseband are. Finding your iPhone model is a no-brainer, but it's possible you have no idea what your baseband is. The baseband, in short, is the computer in your iPhone that deals with broadcast functions, or anything that requires an antenna.

To figure out which baseband is in your iPhone:

• Tap Settings > General > About.
• Scroll downwards until you see Modem Firmware.
• The numbers after Modem Firmware represent the baseband of your iPhone.

Ultrasn0w

Use for iPhones 3G and 3GS, and some iPhone 4 basebands.

Ultrasn0w (or Ultrasnow) is a free unlocking software. Unfortunately, it does not deliver a permanent unlock, but will work well when other unlock solutions aren't viable.

• You will be surprised to find out that many 3GS and 3G models still use Ultrasn0w. Thankfully, these work well enough and the fear of bricking these iPhone models does not exist anymore given Apple's signing rules.
• Practically all iPhone 3GS, 3G and relevant iOS firmware and basebands are compatible with Ultrasn0w. The same cannot be said about iPhone 4 models, however, for which only some basebands are compatible with Ultrasn0w.
• Ultrasn0w SIM unlock is only possible in jailbroken iPhones via Cydia. The exploit supports iPhone 4, 3GS, and 3G.
• iPhone 4S and all iPhones 5 and 6 models are yet to be supported, though the possibility is unlikely. Software unlocks have ceased since iPhone 4 and none of the famed software unlock teams have shown interest in ever walking this path again.

Ultrasn0w-Compatible iPhone Models and Basebands

Most older iPhone models and basebands can be unlocked using Ultrasn0w.

Check the list below to see the supported and unsupported iPhone models and basebands:

iPhone 3GS & 3G

• 04.26.08
• 05.11.07
• 05.13.01
• 05.12.01
• 06.15.00

iPhone 4

• 01.59.00

iPhone 4S: No Ultrasn0w support!

iPhone 5 (all): No Ultrasn0w support!

iPhone 6 (all): No Ultrasn0w support!

How to Use Ultrasn0w

If you're phone is compatible and you are ready to go, start by jailbreaking and installing Cydia. Ultrasn0w unlock is only possible in jailbroken iPhones.

1. Be sure your phone is connected to wireless internet.
2. Activate your iPhone.
3. Jailbreak your phone using Jailbreak Me. Follow these iPhone jailbreak instructions in order to have your iPhone jailbroken and then install Cydia.
4. The above jailbreaking method will automatically install a Cydia app.
5. Select the Cydia icon, and follow the commands to unlock. You may have to conduct some upgrades.
6. When everything is loaded, search for Ultrasn0w in your search bar and select it.
7. Let the program run and reboot your device when commanded to do so.
8. Take your SIM card slot pin and pop out the micro-SIM, replace with your new carrier's micro-SIM.

Important! Preserve Your Basebands

If your iPhone contains any of the basebands listed above, be sure to preserve it every time you restore to another IOS firmware. Every iPhone baseband is upgraded automatically every time you restore your iPhone firmware. You can preserve your baseband by using Redsn0w and other jailbreak tools, or by customizing the IOS firmware.

If by mistake you upgrade your baseband to anything other than what is listed above, you will lose the ability to unlock the iPhone with Ultrasn0w.

Gevey SIM Interposer

Best for iPhones 4 and 4S.

Gevey SIM unlock has been around for quite some time. It's one of the best alternatives to Ultrasn0w, especially when the Ultrasn0w software exploit fails. It 's not a permanent unlock, but will suffice where factory unlock is not available.

Gevey SIM unlock makes use of a specialized hardware interposer: A SIM tray that sits between the hardware baseband of the iPhone and the carrier SIM and performs a Man In The Middle Attack (MITM, see image below). By taking advantage of a few exploits it makes your new SIM relevant to a carrier locked iPhone.

An iPhone unlocked with a Gevey interposer works out of the box with any carrier network SIIM card and does not require the iPhone to be jailbroken.

Unfortunately, Gevey sim unlock is only possible up to iPhone 4S.

A sample Gevey SIM tray interposer which is placed under the unssurpoted SIM card.

Which Basebands Are Compatible

Gevey SIM unlocks are effective in the older iPhone 4 basebands listed here:

• 4.10.01
• 3.10.01
• 2.10.04
• 59 2.10
• 4.11.08
• 4.12.01

And the following iPhone 4S basebands:

• 2.0.12
• 2.0.10
• 1.0.14
• 1.0.13
• 1.0.14

R-SIM Interposer

For iPhone 4S and all 5 models.

R-SIM interposer is a popular method to unlock iPhone 4S and 5 models, picking up where the Gevey sim interposer stopped. Versions 7, 8, and 9 will also unlock iOS 7 models.

This interposer can also be used to activate stubborn iPhones, especially those from Sprint.

Sample R -SIM 7+ interposer for iPhone unlock.

How to Use

Unlocking the iPhone with an R-SIM interposer is simple:

1. Place your new macro SIM (iPhone 4 or 4S) or nano SIM (iPhone 5) onto the interposer tray.
2. Slide the tray back into the iPhone and follow the simple instructions that follow.
3. You will be prompted to restart your iPhone to complete the unlocking process.

Problems Unlocking Sprint iPhones

You may encounter issues when activating and unlocking Sprint phones. In case this happens, the voice calls will function normally but SMS and data services may not.

To solve the problem, you will have to download the free activation patch application and buy an activation code from the R-SIM website.

IMEI Number

Factory unlock for almost all iPhones.

Also called iPhone factory unlock, the unlock via IMEI number is the ultimate permanent unlock. Apple sanctions factory unlocks through its carrier partners.

Read through this list of carrier networks offering a variety of Apple-related services. One of the services includes unlocking the iPhone. Cross-check with your relevant carrier network for pre-qualification and then proceed with the rather brief instructions to back-up your apps and data before unlocking the iPhone.

This unlock only works if you have fulfilled the following conditions:

• You should be a customer with an Apple carrier partner and your account must be in good standing, with your phone bills paid.
• You can unlock your iPhone with AT&T even if you are not a customer with them, as long as you have completed your old contract or if you purchased your iPhone with no contract.
• One other important caution is that you must be sure that your iPhone is not stolen or blacklisted. A stolen iPhone that was reported to relevant carrier network will be discovered and you can get into trouble for it.

Check the iPhone IMEI Number

You can find the IMEI number of your iPhone in a number of ways. This is the easiest:

1. Type *#06# on the dial screen.
2. Your IMEI number will appear in a flash.

Factory Unlock Websites for iPhone

If you wish to unlock your iPhone using the IMEI number be warned of scam websites out there and proceed at own risk. I have listed a few websites which have received recommendations from many users, but do not take my word for it. Always proceed with caution.

1. Chronicunlocks
2. GSMunlocking
3. MyIMEI unlock
4. iPhoneIMEI dot net unlock
5. AT&T

The iPhone Wiki maintains lists of hundreds of fake unlocking and jailbreaking sites. You may want to visit it and stay above the scam threats.

SAM Ticket

SAM Unlock was an exploit that worked perfectly until April 2012, when it was patched by Apple.

Despite this, many informed users who installed SAM in their iPhones saved SAM tickets using Cydia. Having the tickets already installed enabled users to unlock their iPhones even after upgrading their iOS firmware. Those who saved their tickets can still, and will always be able to unlock their iPhones using this exploit.

SAM only works in jailbroken iPhones. The usual advice is that you should never upgrade to any iOS which does not have a jailbreak if you depend on SAM

Source: http://hubpages.com/technology/How-to-Unlock-iPhone-4-Using-Ultrasnow-iPhone-IMEI-and-Gevey-Sim-Tool