A call is established between a user at a mobile device and a contact logged into a communication service through a computer application. A user selects a contact through a page displayed on a mobile device. The contact may be an email address, a messaging username, or some other contact other than a phone number. A call registration record with the contact data is generated at a network server. The mobile device places a call to a VoIP system, the VoIP system receives the call, retrieves the call registration record and establishes an audio connection between the cell phone and the computer application through which the contact is logged into the communication service. The audio connection is a hybrid connection consisting of a mobile device voice connection between the caller's cell phone and a gateway system and a VoIP connection between a computer and the gateway system.