Skype prevented users from making calls over 3G data networks on the iPhone for contractual reasons, but I think many would love to have it working. Here’s a summarized version of getting Skype to work on the iPhone.

I’ve tested it on the 2G and it seems to work, though voice call quality is choppy.

The pre-requisite here is to have a jailbroken iPhone with Cydia installed, and also knowledge of basic UNIX command line and the VI editor.

If you do not have a jailbroken iPhone, do not ask for instructions here. You should find them online elsewhere.

1. Install or update to the latest version of MobileSubstrate via Cydia. This fixes a crash on Skype.
2. Install VoIP3G via Cydia. This enables you to make VoIP calls via 3G.
3. Install SSH and VIM Enhanced via Cydia. You will need this to edit some files in your phone.
4. Connect to a Wi-Fi network, preferably the same network as your computer.
5. Get the phone’s IP address under Settings > Wi-Fi.
6. SSH to the phone as root with the password alpine (this is the iPhone default if you haven’t changed it).
7. Go to /Library/MobileSubstrate/DynamicLibraries and edit VoIPover3G.plist.
8. You will see a line that looks like the following…
   Filter = {Bundles = ("com.Fringland.Fring");};
9. Appened “com.skype.skype” to the array (it might already be there), e.g.
   Filter = {Bundles = ("com.Fringland.Fring", "com.skype.skype");};
10. Save the file, restart your iPhone, and reinstall Skype.