USB communication with iOS and without MFi

Hello, we are designing HW product with functionality similar to external USB sound card. Our device needs to work with iPhone and iOS. W plan to use MFi certified Lightning to USB cable available from Apple. Because of extended features we need to somehow configure them. So the plan is:

  1. use USB Audio class for audio transmission.
  2. implement some kind of communication channel to control extended features of the device. It can be:
  • CDC (serial) class,
  • vendor specific class,
  • HID class,
  • USB control pipe messages.

We can implement whatever is needed, because HW and firmware is created by us.

And now a questions:

  1. What kind of communication channel would you recommend, what is possible?
  2. Can such a communication channel work with iOS?
  3. Can such a device be introduced to a market without participation in MFi programme?

I have found similar questions / threads on this forum, but they are either 5 years old or there is no answer.

https://developer.apple.com/forums/thread/93395?answerId=282802022#282802022

https://developer.apple.com/forums/thread/719492

The only recent one with answer is this one:

https://developer.apple.com/forums/thread/701434

USB communication with iOS and without MFi
 
 
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