In at least some embodiments, a system includes at least one server to manage voice over internet protocol (VOIP) services. The managed VOIP services provided by the at least one server include a telephony service to establish a calling phase between an initiator device and a mobile target device in response to a call command received from the initiator device, and a streamline call transfer service to transfer a call from the mobile target device to a transfer target device in response to a one-touch transfer command received from the mobile target device during the calling phase.