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I am currently writing a iPadOS application to act as a companion to the desktop version that controls a piece of hardware via a USB CDC serial connection. Due to modern iPads having USB-C ports for the last 2 years and the ability to attach certain USB devices via adaptors since the origin of the 30pin doc connector I would expect protocol availability to be fairly complete. So then why is it that the headers required to use USB CDC serial don't exist and if you make them yourself you need to use illegal symbols so you can't upload it to App Store connect. Where as USB CDC ethernet has full support along with Bluetooth RFCOMM (rs232 serial over bluetooth) and even USB MIDI given that midi is a superset of serial. So why isn't there a USB CDC serial kit/api/even just allowing a data stream to the TTY/CU port? If there is a way please tell me what it is and point me to the documentation.