Please view my videos on your computer, the annotations within the video will not display on any mobile device. Sorry. Please like and subscribe if you thought this video was helpful. First, your gonna need your device jailbroken and running 4.x.Next you’ll need to disable 3G because the iPhone is incompatiable with T-Mobile’s 3G network and can’t be used. MY IPHONE SAYS 3G BECAUSE IT IS A THEME IN WINTERBOARD TO GET RID OF EDGE ICON TO 3G ICON. So Open Cydia, and add this source “bbyscroopy.pirat3.com and install the package “i4mms”. Next go to your springboard and find T-Mobile and open it. Select Apply Settings and the device wil respring. Next go into settings and select General and then Network and finally Cellular Data Network. In there scroll to the bottom and select Reset Network Settings until the empty fields fill up. Usually once or twice. Next open Browser and try using your internet. good luck. … if it says Upsell Required. you either dont have a data plan set up or you need to call 611 and tell them your new IMEI number. THEY DONT CARE THAT YOU HAVE AN IPHONE. THEY WILL HELP YOU 100% GETTING INTERNET WORKING. THEY JUST WONT HELP YOU UNLOCK IT SO DONT EVEN BOTHER ASKING THEM THAT. Also , if your using Gevey Sim on the new iPhone 4 and the Cellular Data Network disappears. Just redo the T-Mobile icon and respring and it should show up.
Read more from the original source:
How To Set Up iPhone Internet / MMS On T-Mobile USA