Using an iPhone 5s with the latest 3CX iphone app. Have registered the extension and have successful connection while on our internal LAN. While on LTE or 3G the extension status is showing Connecting then Timeout constantly. thought we had resolved by allowing extension outside of LAN setting under extension options but symptoms are still the same. It appears that internal calls to other extensions is working (at least ringing). Just want to see what this issue may be before deploying demo to site.