Or, is there any way a user would be able to tell? ie any commands I can run on my Mac to output some info that might tell me, or anything I can look for in the logs? I know how to increase the logging for each of the 'subsystems' (is that the right term?) - if the logs that might show this info are not output by default..

Would you be comfortable giving a rough estimate based on just what you know about them (even if that is simply seeing their App Store page and reading this thread) combined with your knowledge on iOS development technologies and what you know? Alternatively, would you be comfortable giving a rough estimate about how likely any app would be using usbmuxd if that app was able to communicate with a companion Mac app via USB (ie in a general sense - not in reference to any particular app) eg. very likely, likely, maybe, not sure, unlikely, very unlikely? I'm not looking for anything that's a sure thing, but if you feel you're comfortable to give a rough estimate, and you were also ok to give one, please do. I understand if you'd prefer not to though. Based on your posts in this thread, it seems like there really isn't another way to do this other than usbmuxd. So it seems either likely or very likely that's what they are using? I've only used one of the apps and it only works when you open the companion app on Mac (and PC). Using an Ethernet cable could be a way forward - yep.. Using an Ethernet cable with an iPhone is just like plugging it into your Mac - as in, there is nothing different an application would need to (just deal with sending network packets) - the OS handles everything else?

Thank's eskimo So for the apps that do achieve this [1][2], are you implying they are almost certainly using usbmuxd? If this method isn't supported, how does it get past app store review? Also, on the chance that part of my post hasn't come through clearly: I would be Ok with the connection between the iPhone and Mac wasn't to use raw/native USB - but the preference is that it happens over a cabled connection.. I'm interested in: Ability to send video and audio from the iPhone to the Mac over a cabled connection Ability to send commands from the Mac to the iPhone that the app will use to make adjustments to the video/audio stream If it's not possible over a raw USB protocol/mechanism - is there any other mechanism that would allow this over a cabled connection? Preference here is USB (utilising the users existing iPhone cables) but if that's not possible would any other types of cables allow something like this? The idea is to use the iPhone camera for live streaming, and allowing the user to adjust settings (quality, zoom, etc) from their computer without needing to get up and touch the iPhone.. With a user likely streaming via their network (WiFi), I'd prefer to not send the video/audio stream over WiFi [1] https://apps.apple.com/us/app/id1352834008 [2] https://apps.apple.com/us/app/id1524933155