DynDNS with mobile connections usually doesn't work. All (swiss) mobile providers route their mobile traffic using NAT, i.e. the IP which your browser shows on some IP-detection service like https://www.cyon.ch/misc... is not the IP of your device, but the IP of some NAT router at your mobile provider's data center. Thus, using DynDNS you would just point your DNS name to the mobile provider's data center, but requests to that IP will never be routed through to your device.