Hi whitezryder,
The "external address" will not populate if Sighthound Video was unable to open the port in your router on it's own, even if you manually forward a port. When you attempted to connect with your phone. With port forwarding configured you should be able to connect with your phone on the cellular network by entering your networks external address (www.whatsmyip.org) with the port that is forwarded to Sighthound. (external.ip.address:port)
Are you able to connect to Sighthound with your phone by using the "internal address" while connected to the same network?
Regards,
-Devin
