US Patent 9077785 Originator mobile device assisted voice call technology selection

A smart Voice Over LTE (VoLTE) application for allowing a wireless mobile device to select an appropriate access technology for establishing a voice call with a target mobile device, based on the capabilities of the target mobile device. Selection on the client side allows interoperability of a VoLTE wireless mobile device on a circuit switched network without requiring use of a gateway between the circuit switched and VoLTE networks. If the target mobile device is only configured for legacy circuit switched network calls, the wireless mobile device need not begin the call connection on the VoLTE network and instead may establish the call on the circuit switched network from the beginning.