First off I would like to give credit to ZekeFSM at funkyspacemonkey because of his tutorial is the old method that doesn't exactly work anymore, so I made a tutorial that works right now. Hey you guys I just purchased an iPhone 4 on Tuesday, I checked out out a few threads on here and decided to try and get the unlimited plan because I want to teather without worrying about going over the 2GB limit. This works on iPhone 3G, 3GS, and 4 This is for people who currently have the 2GB/200MB data plan and want unlimited data for $30 What do you need if you have an iPhone 4? -Access to an iPhone 2g(1st Gen) -Access to a phone that you don't need a data plan on to use -Your iPhone -Credit card or microsim -> normal sim adapter -Exacto knife, razor, scissors What you need if you have an iPhone 3g/3gs -Access to an iPhone 2g(1st Gen) -Access to a phone that you don't need a data plan on to use SKIP TO STEP 2 IF YOU DO NOT HAVE AN IPHONE 4 or microsim Step 1- You will need to cut out of a credit card or a thin plastic material with the same thickness of a sim card to get the microsim to fit into a normal sim phone. Or if you can't then buy a microsim adapter. I personally just cut and made my own adapter from a credit card. You should get something like this Step 2-Put your iPhone simcard into the phone that does not need a dataplan, not an iPhone. If you were using the adapter because you have an iPhone 4 sim it should show that you have service, if not the sim is not touching the pins correctly inside of the phone. It may take multiple tries to get it to fit properly. Step 3-Call up ATT and tell them that you don't want a dataplan because you got rid of your iPhone. They should remove the data plan. After they did check your online account just to make sure. Step 4-Put the simcard inside of the iPhone 2g, and turn on so you have service. Step 5-Call up ATT and tell them that you would like a data plan on your iPhone 2g. The only data plan possible for it is the $20 unlimited plan. Make sure you see the $20 unlimited plan on your ATT account online. Step 6-Put the sim/microsim back inside the iPhone 4/3g/3gs and wala, in 5-12 hours you should get a text saying that you were put on a compatible data plan for your iPhone. Now you are subscribed to the $30 dataplan. Please be patient if it has not switched over yet. Step 7-Congratz you now have the unlimited data plan, stream videos all you want and download as much as you want.