Earlier this week, Comex have released the new web-based jailbreak on the web. So what is the killer feature if you get your iPhone 4 jailbroken? FaceTime, you can now do FaceTime on 3G network and no longer need any WiFi Connection!
Steps to achieve it:
1) Jailbreak your iPhone 4 via www.jailbreakme.com.
2) Download and upgrade to the latest Cydia package.
3) Open Cydia, Go to Manage then Sources.
4) Click Sources, Edit then add: http://apt.modmyi.com
5) Search for “My3G” — download, and install it.
6) Go through the Rock setup process with a username and password. Open My3G and leave all settings on the default.
7) FaceTime should now work over 3G! — Make sure to “Forget” the WiFi network you are on (via iOS settings) if you want to test it.[9to5mac]