Earlier this week I showed off my iPhone with data only and the benefits of the device. Now I am here to show you how it actually works in a step by step tutorial for those who have been asking. 

Needs: You'll need an AT&T microSIM card, if you need a new account then you'll need an unactivated SIM. You may also use an existing active SIM. An iPad 3G is needed to activate an unactivated card. If you don't have an iPad you can buy an iPad 3G and return it without the SIM or use a display iPad in certain stores. You will also need an iPhone with 3G capabilities. 

1. Activate the SIM card in the iPad by setting it up in the Settings application. (Skip this step if you have an already activated SIM).

2. On your iPhone while connected to Wi-Fi go to unlockit.co.nz. On the web app tap continue, custom APN and choose your country and carrier. Then you tap create profile. This installs the APN on the iPhone, you may need to enter your passcode if you have one. After the APN is installed turn on Wi-Fi so you can correctly test the network connection after the next step. 

3. Remove the SIM from the iPad 3G and put it in the iPhone. Wait for the iPhone to find the network, which can take up to many minutes. 

4. Test, while making sure Wi-Fi is off open Safari and try to load a webpage. If it loads then you have correctly done the process and can use your iPhone with data only. If you can't load a webpage make sure you have done all the steps correctly and 3G service is available in your area.

That's all you need to do in a very small number of easy steps. If you are having problems ask in the comments below or contact me on Twitter. We must warn that this most likely breaks AT&T's terms and conditions you agreed to when activating a SIM card.