What does it mean when you are unblocking or unlocking your iPhone?

Note that unblock and unlock are used synomously throughout this article.

Apple signed a contact with AT&T Cingular where only AT&T Cingular had the exclusive and authorized right to be dealers to sell iPhones with a phone contract. Because of this contract between the two parties, Apple has made it so that the iPhone only works with AT&T Cingular as the carrier or network.

This sucks if you are on another carrier like T-Mobile where you get charged an Early Termination Fee (ETF) if you break your plan early to switch to AT&T Cingular. Not to mention AT&T Cingular requires you to get a data plan on top of your individual plan. Plans can then range from $70 to $130 a month and this is not including added features like text messaging or voice dial.

If you already have a data plan with another carrier and want to switch phones, your best option is to unblock or unlock your iPhone.

There are two ways to unblocking your iPhone:

1. Software Hack

2. Hardware (a thin SIM card that goes underneath your carrier’s SIM card)

Unblocking your iPhone using a Software hack.
To unblock your iPhone to be used with a different carrier, first it needs to be Jailbroken. What does it mean to jailbreak an iPhone? Jailbreaking allows unofficial code to override the software installed on the iPhone.

With that, you can then install third-party apps and use another installer called Cydia, rather than just Apple’s App Store installer. So the reason the jailbreaking needs to be done is to install a 3rd party app which unblocks your iPhone to be used on any carrier.

Note: jailbreaking or unblocking your iPhone via software hack may void your warranty with Apple.

To jailbreak your iPhone with Windows, use this tutorial How to Jailbreak your iPhone or iPod Touch for Windows

If you have a Mac, there is a tutorial with videos in this article How to Jailbreak your iPhone or iPod Touch for Mac

After you have jailbroken your iPhone using the tutorials above, you can do a software hack to unblock your iPhone.

Very important: Do NOT update your iPhone in iTunes. It must be at baseband 2.28.00 or lower. Check your baseband by going to Settings->General->About.

Now you can begin unblocking your iPhone with this unblock tutorial How to Unlock Your iPhone 3G

Pros: Unblocking this way is very reliable. It works most of the time and does not drop off. You can download and install third-party apps, and also download and install paid apps for free.

Cons: You need to keep your baseband at 2.28.00 or lower until the Dev Team who creates yellowsn0w comes out with a new hack. You are totally dependent on their releases. You may void your warranty.

Unblocking your iPhone using Hardware hack

The hardware hack consists of a thin filmy SIM card which is placed underneath your existing SIM card. When the card is insterted, it overrides the blocking capabilities of your carrier’s SIM card. Thus allowing your to make and receive calls, use your data plan, and send out texts without much problems. Some of these SIM card companies are called: GEVEY SIM and Rebel SIM.

Pros: No need to do any software hack that may turn your iPhone into a pretty paperweight. Will not void your warranty.

Cons: Very unreliable. Will work for a few days and then when your SIM card tries to contact the network, it will drop off unexpectedly.

Those are the only two ways to unblocking your iPhone. You have to be careful when you are doing these because there are a lot of legal issues surrounding unblocking your iPhone. But as my Uncle Larry used to say: “It ain’t illegal unless you get caught!”