I just had a chance to access my home PC using VNC over 3G. I was able to play with it only on local network before.

What you need… on your ubuntu machine

• Remote Desktop (vino)
• System > Preferences > Remote Desktop. Check “Allow other users to view your desktop”. And best if you set a password and uncheck “Ask for confirmation”.

On your iphone…

• Mocha VNC Lite http://mochasoft.dk/iphone_vnc.htm
• Add your connection preferences.