Cavit Ribbon is a Transpose and Ribbon Controler app for all Midi Keyboards Feature-List: - Ribbon Cotroller - Transpose Function button - Interfaces compatibility Yamaha - MD-BT01 Wireless Midi Adapter, Quicco Sound mi.1 Wireless Midi Adapter, Apple Lightning to USB Camera Adapter (iPhone/iPad), Apple Lightning to USB 3 Camera Adapter (iPad) The application to be used in conjunction with compatible interfaces.