More than a million people have purchased an iPhone in the US since the end of June, and they all had to sign up with Apple’s exclusive carrier in the US, AT&T. Those Apple iPhones hook up to AT&T’s network using an AT&T SIM card, and limit users to that network. Today, Apple will announce the UK version of the Apple iPhone, with O2 taking the role of exclusive carrier.

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Break free

But what if you’re planning a trip abroad and, rather than paying O2 to use the networks of its European partners, you want to take advantage of the favourable rates and local phone numbers offered by replacing your O2 SIM card with a pre-paid European card? Or what if you’d prefer to use Vodaphone or Orange as your cellular provider, rather than O2?

See also: How to protect your iPhone from Theft

In the past month several groups have announced that they’ve found a way to "unlock" the iPhone, allowing it to use a SIM card from any provider. (Keep in mind that this is only half the story: the iPhone uses the GSM radio band for its communications, meaning that it’ll work only with mobile phone providers that use the GSM network. Check with your chosen provider before you start to hack.)

In August, a group of hackers demonstrated a method for unlocking SIM cards and sold its software to resellers, who in turn began selling the iPhone hack to the public for as little as £25.

But another group has came up with its own hack that, with the help of some free, open-source software, lets you unlock your iPhone in about an hour, free of charge.

Below, we’ll show you how it works — and it does work, because we’ve used this technique to unlock an iPhone. (One important caveat: in the US certain AT&T-only features, such as Visual Voicemail, will not work when you’re connected to other cellular networks. At this stage we can only speculate as to the effect on an O2 iPhone.)

Before we get started, you’ll want to disable the iTunes helper application that may get in the way of the installation. To turn off iTunes Helper, go to Start, Run, type in msconfig, click on the Startup tab, and uncheck iTunesHelper from Startup Item list. On a Mac, make sure iTunes is not running, then open OS X’s Activity Monitor in the Utilities folder of the Applications folder. Search for or scroll down to iTunes Helper, select it, and then click on the Quit Process button in the top left of the screen.

You’ll also need your iPhone, your data cable, and a Wi-Fi connection to the internet.

(If you haven’t already activated your iPhone with O2 — and aren’t planning to—you need to conduct a fake activation. To do this, you’ll need to follow the excellent instructions at ModMyiPhone.)

Install AppTapp

Apple doesn’t support the installation of third-party applications on the iPhone, but the enterprising developers at NullRiver have created a program called AppTapp that will let you install including chat clients, games, and other pieces of software — including those that are needed to unlock your iPhone.

Download and install AppTapp. Once you run the program, the first thing it will do is ask what version of the firmware you’re running. If you’ve just updated your iPhone, you probably have Firmware 1.0.2 - select that and click on Continue.



AppTapp in action

Assuming all goes well, you should get a screen that begins with the words: "Congratulations! You have successfully installed AppTapp Installer on to your iPhone." You should then find a new application on the iPhone’s home screen called Installer.

The next instructions will require downloading some applications from the internet to your iPhone — so make sure your iPhone is connected to a Wi-Fi network. Launch the Installer program, and you’ll see a long list of various applications that you can install. Scroll down, then select and install — in order — Community Sources, BSD Subsystem and OpenSSH.

Turn the page to perform the next stage of your Apple iPhone unlock