The link is as follows: app store: monitor+
I have checked the header file for USB in the IOKit framework of macOS, but it does not exist in iOS. Is it necessary to collaborate with Apple to implement functions similar to monitor+(PTP control camera)?
It sounds like you want something like IOUSBLib, but for iOS/iPadOS. I want that too.
You can write a camera extension, but only for cameras that you own (your company has the USB vendor ID). The dext will only load on devices with an M1 or M2 processor.
If you would like something like IOUSBLib for iOS, please file a feature request.