Unlocked Apple iPhone 3G
Most iPhone users will be aware that there are a number of unofficial ways to unlock an iPhone 3G.
First of all you have to download the Quickpwn tool to jailbreak to your i-phone, you can download it from apple’s website.
Now connect your iphone in pc or laptop from usb, Then The Quickpwn tool to jailbreak will recognize the i-phone.
IPSW is built and then data + firmware is sent from your computer to the apple website. Then it will need you to do a few things with your phone(like holding the center + switch off button for 10 seconds and releasing). With all this done,
Now after to do this process you need to install Cydia to your SmartPhone. Through the installer app in your phone, you will see it already there. Install and then select Cydia from the list of apps in your iPhone.
On the bottom of Cydia page, go to Manage.
Then go to the Sources window, and click Edit on the right.
Then Select the added URL and you will be taken to the yellowsn0w download window.
Click on Add and then enter the Cydia/APT URL = http://apt.yellowsn0w.com
After saveing it you have to fallow these process
Go on the Settings >Select the General > then Select the Reset > Then Reset Network Settings
Now you have to Switch off your iPhone and place the 3rd party SIM into the socket and switch it on. The phone will not recognize the SIM, Now go to Settings Tab and Switch On and Off the Airplane mode and wait for a responce.
After this, remove your SIM with the phone On, and re-insert it. Wait for a minute and you will see your network active. Be patient for a minute or two, so that your phone recognizes and establishes connection with your SIM and network.