Conversion of mobile device to LAN-only telephony functions

In a mobile device, the method of:

• determining whether the mobile device is configured for communication over a cellular network connection, the mobile device being configurable for communication over at least one cellular network and over at least one wireless LAN, the mobile device being configured for voice communication using at least one mobile telecommunications standard and at least one IP-based network;
• determining whether the mobile device is configured for communication over a wireless LAN connection;
• and
• configuring a user interface to reflect current voice communication availability with a cellular telephone number associated with the mobile device when the mobile device is determined to be configured for communication over the cellular network connection;
• and
• configuring the user interface to reflect current voice communication availability with a direct inward dial number at a PBX associated with the mobile device when:
• the mobile device is determined to be configured for communication over the wireless LAN connection, or
• the mobile device is determined to be configured for communication over the cellular network connection and connectivity is available over the cellular network connection with the PBX,
• the configuring of the user interface including displaying icons selectable to invoke corresponding service entry points for those telephony services for which the mobile device is currently configured and for which connectivity is available.