The present disclosure provides systems and methods for communicating with a hotel, for example, by establishing calls from a mobile communication device as an extension of a PBX of the hotel. The mobile communication device can receive, by a network interface, guest registration data for a guest of the hotel, including the room assignment and one or more guest service extensions on the PBX. The mobile communication device can store the guest registration data in electronic memory to configure the one or more guest service keys with the one or more guest service extensions. The mobile communication device can based on a selection of a key of one or more guest service keys, communicate directly with the PBX, by the network interface, to place and receive calls as an extension of the PBX associated with the hotel room assignment.