Unlocking the iPhone might make it vulnerable to certain threats. Still you might want to unlock your iPhone, solely to counter one Apple whim – carrier exclusivity. You don’t want to change your trusted carrier (and spend a huge lot more), in order to enjoy (and flaunt) an iPhone.

Unlocking the iPhone is not that easy, However, as we have posted earlier, there are a number of services which let you unlock your iPhone .  The best way till now is to use the method that the guys at the iPhone Dev team have figured out – through the yellosn0w application, which is available via Cydia.

The yellosn0w application works only on the 2.2 farmware and above and you need to jailbreak your iPhone to use this method. Use QuickPwn to jailbreak your iPhone as that will automatically install Cydia to your iPhone.

After jailbreaking you need to go through the following steps:

1. Go to your iPhone’s home screen and launch Cydia

2. After Cydia is launched, tap “Manage” and then “Source” to go to the “Edit” and finally to “Add”.

3. Add http://apt9.yellowsn0w.com/url as the source url for yellowsn0w and add it by tapping the “Add Source” button.

4. Now press “Return to Cydia” from the bottom of the screen and tap “Done”.

5. Now tap http://apt9.yellowsn0w.com/url till you see the option to install it. Once this app is installed, again tap the “Return to Cydia” tab from the bottom of the screen.

Voila? Not yet. You need to reboot your iPhone 3G first, then shut it down , insert you preferred SIM and then restart it. You should now see the “slide to unlock” option and, hopefully, the signals of your new carrier. That’s it (if it works on your device that is…)