It may be that something has changed with your network configuration or perhaps your mobile carrier. On the iCamSource Mobile, if you browse to Options > Advanced, do you have either the Auto-Config Router or Port Forwarding enabled?
If not, if you try turning on the Auto-Config Router switch before tapping Start, and are you then able to connect from a different network? If not, what is the message that appears underneath the Auto-Config Router switch after you have started the iCamSource Mobile? (You'll have to navigate back to the Options > Advanced screen after tapping "Start".) If it doesn't say something similar to "UPnP Success" then your router was not properly auto-configured to receive the connection from outside of your local network, and manual port forwarding may another solution.
