Sony make a software development kit called 'camera remote'
So I got all excited. Perhaps I could write my own iPhone app that replaced the basic Sony app.
Unfortunately this SDK does not permit the developer to transfer images from the A7RII to the mobile device, so that scuppers it. The transfer image function is only available for some compact and lens type cameras such as the QX10, QX1 etc.
That means you'll have to wait until Sony release a compatible version of their own app.
My biggest desire was to find a way of saving the additional custom setups persistently on a mobile device as currently M1-M4 are stored on the memory card and deleted when the card is formatted! Brain dead concept.