The Accsoon SeeMo is a device that lets you add an iphone as a monitor for your camera. You can also stream with it.

See here: https://accsoon.com/accsoon-seemo/

The question now is: would vmixcall (advanced.vmixcall.com) in desktopmode see this camera as an available input to select for vmixcall

(in advanced you can select any camera the iphone had fron back wide portret).

That would be a gamechanger so you could use vmixcall as a way to add a professional camera wirelessly.

cheers, stefan