Jailbreaking vs. Unlocking

For the uninitiated, "jailbreaking" refers to the ability to open up a device in order to install unapproved, third-party applications. Given both AT&T and Apple's restrictions regarding the iPhone, this process is a must for many Apple device owners.

Jailbreaking allows access to many new functions, including turning the phone into a Wi-Fi hotspot, being able to fully customize the phone down to its icons, forcing Wi-Fi only apps to run over 3G and, for those whose older devices don't support all of iOS 4's new features, jailbreaking offers some viable alternatives. 

Jailbreaking and unlocking the iPhone are two different hacks which allow you to take control of your mobile device in different ways. Jailbreaking, as noted above, is a type of hack that lets you install unapproved third-party applications on your iPhone or iPod Touch from searchable repositories provided by apps like Cydia and Icy. Unlocking, on the other hand, is a hack that lets you use your iPhone on another cellular network. Here in the U.S., that means you can use the iPhone on T-Mobile instead of AT&T. You have to first jailbreak your phone before you can unlock it, but you don't have to unlock a phone in order to jailbreak it.

How to Jailbreak with Sn0wbreeze

The "sn0wbreeze" jailbreak software has a very specific use case. You can only use it if your phone has already been jailbroken and if that jailbreak was not performed using the popular jailbreak tool called "Spirit." It is also a Windows-only software program.

To be clear, if you have an iPhone 3G, iPhone 3GS or iPod Touch that's already jailbroken with redsn0w or the Mac software called Pwnage Tool, you can use sn0wbreeze. It also does not work on "MC" model iPods - those whose model numbers begin with the characters "MC." To check your device, go into "Settings," "General," "About," then scroll down to "Model Number."

If your device fits these specific parameters, here's how to do it:

1. Download and install the most recent version of iTunes first and back up your phone. Do not upgrade your phone's firmware to 4.0 at this time.
2. Download sn0wbreeze from the ih8sn0w.com homepage here.
3. Download the iOS 4.0 firmware. (Links available here and here and elsewhere on the net. Remember, you're downloading the iOS 4.0 firmware for your device, older versions or those for other devices don't work.)
4. Run the sn0wbreeze executable you downloaded.
5. Choose "Simple Mode" from the first screen of the setup program.
6. When prompted, point it to the iOS 4 firmware file you just downloaded. The software will verify the file and then you can click "Next" to continue.
7. On the following screen, click "No" on the pop-up message that appears if you are using your phone on an official carrier (like AT&T in the U.S). Click "Yes" if you want to use your phone on a different carrier.
8. The software will then proceed to jailbreak your iOS 4.0 software file.
9. The final step is to restore your phone to the now-jailbroken software. Connect your phone to your computer, launch iTunes and select your phone in the left-side menu of iTunes.
10. Hold down the SHIFT button on your keyboard while clicking on the "Restore" button in iTunes. Then let go of the SHIFT button. 
11. iTunes will now prompt you to select the location of your custom firmware file (the now-jailbroken iOS 4.0 software). Direct it to wherever you had originally downloaded that file and click "open."
12. iTunes will now "restore" your phone to that jailbroken version of the iOS 4.0 firmware. Do not do anything else on the computer while this is taking place.
13. When the process completes, your phone is jailbroken. Those who then want to then "unlock" their phone for use on a non-standard carrier (like T-Mobile in the U.S.) will need to follow further instructions to do an unlock. This guide can help.

Keep in mind that if you have a jailbroken phone, you can't get support from Apple for any issues you may have. However, jailbreaking isn't permanent. You can revert your phone to its factory settings at any time via iTunes with no one the wiser.