An app should* be able to interface with iOS via Bluetooth. *I don’t know if the chipset can support this.
You caught yourself! I think there would be to many problems trying to get the app to communicate over Bluetooth and the audio going at the same time. I also don't know if the chipset would support it too, I just know that every time people ask Audeze there response is always PC at launch and Mac & Android later on. They purposely avoid addressing iOS every time, even when people specify it. I think if they could do it they would, it just probably isn't possible.