Abstract: A variety of methods, systems, devices and arrangements are implemented for communications using a mobile communications device. In connection with various embodiments, one such method relates to routing calls specifying an endpoint device, from a mobile communications device to the endpoint device, using a call forwarding/routing service provider that establishes a connection with the endpoint device. The established connection may include, for example, a Voice-over-Internet Protocol (VoIP) connection. In some implementations, the authentication server is contacted (e.g., via the Internet) to authenticate the call to be made via the call forwarding/routing service provider.