OP-Z controls DrossDj app
This setup creates a virtual MIDI controller and tricks CrossDj into accepting it as its mine controller.
Than controllers are remapped to fit into the op-z interface.
You need Midiflow app for this !
Just open file on your iOS device, and open it with Midiflow.
It will create a new setup that links op-z controls with CrossDj
Channel 15 control channel for CrossDj app
You can change the channel number or some other stuff in the initial setup.