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.

I use CMIOObjectAddPropertyListener for this kind of communication (of state changes from the extension to an app). That said, I'm surprised at this line [mObserverClassInstance subscribe:@(notification.c_str())]; because I thought @ could only be used with string literals, so you could write [mObserverClassInstance subscribe:@"VirtualCamUsageChanged"]; I've never seen @ used with a run-time expression.

It is a provisioning profile for the app, not for the device the app runs on. The profile ends up embedded in your app (in the bundle, in a .embeddedprovisionprofile file).

how exactly do you determine that the joystick "does not work" on macOS? Joysticks are not directly supported by the OS, you need to have code that specifically looks for input from HID joysticks. Do you have such code? There's an old project on GitHub https://github.com/arsdraconis/HID-Explorer which needs a few changes to compile on modern macOS, but you may be able to use this to get more insights into how your device is treated by the OS. Also, see this post on Stack Overflow: https://stackoverflow.com/questions/41715074/simple-hid-osx-application, which refers to the open source parts of IOHIDFamily.

Could you rephrase your question? What communication issue are you referring to? How does MFi play into this (there is a separate section of the forum for MFi-related questions). What exactly do you need help with?

If you insist, Qt is a cross-platform C++ framework for app development which can target macOS. However, I think you're rowing against the tide here. Current documentation and online articles about macOS development lean towards Swift (ten years old) and SwiftUI (five years old), and Objective C. You can use C++ with ObjC code, just change the file extension from .m to .mm. I don't think it is possible to write any meaningful app without using a library of some sort. What exactly are you trying to avoid?

I filed a bug with a minimal macOS project with a DriverKit dext which exhibits this same behavior, FB13688443

are you sure you have a ContentView.swift file on disk? You say "all my files were gone" but I only see one that Xcode can't find. Where does Xcode think it is? Click on the file ContentView in the file navigator on the left, open the inspectors panel on the right, select the File inspector (the first one). You'll see the Full Path - does it lead where you expect? If the file is present on disk, you can update the path by clicking the little rightward-pointing arrow in a circle next to the path and selecting the file in its actual location.

if you think you've found a bug, file one using Feedback Assistant. Bugs you report here are not entered in Apple's bug report tracker.

this looks a little odd to me: "Could not find the main bundle or the Info.plist is missing a CFBundleIdentifier in \U2018MyApp.productbuild.pkg\U2019."; because it is presenting the name of the package inside quoted Unicode LEFT SINGLE QUOTATION MARK and RIGHT SINGLE QUOTATION MARK. I'd expect plain quotation marks. Take a careful look at the contents of your scripts and make sure you're not copying a command line from a text editor (such as Word) that likes to convert written ' and " to curly quotes.

Core Specification Supplement 11 (https://www.bluetooth.com/specifications/css-11/) page 16 (Part A, Section 1.4.1) "The first two data octets shall contain a company identifier from Assigned Numbers. The interpretation of any other octets within the data shall be defined by the manufacturer specified by the company identifier."

something like this should get you started. You'd probably want to put any custom colors into an Asset, not hard-code them like this. All the colors I made here are transparent, so my white background shows through. I found many relevant samples quite quickly by searching the Internet for "SwiftUI gradient" and "SwiftUI custom color" and "SwiftUI filled rectangle". Did you do the same? If you didn't, you really should have... extension Color { static let pink = Color(red: 0.8, green: 0.0, blue: 0.0, opacity: 0.3) static let reddish = Color(red: 1.0, green: 0.0, blue: 0.0, opacity: 0.5) static let darkishRed = Color(red: 1.0, green: 0.0, blue: 0.0, opacity: 0.3) } let gradient = LinearGradient(gradient: Gradient(colors: [.pink, .reddish]), startPoint: .top, endPoint: .bottom) struct ContentView: View { var body: some View { ZStack { RoundedRectangle(cornerRadius: 10) .fill(gradient) .frame(width: 200, height: 200) Text("hello world") .font(.largeTitle) .foregroundStyle(Color.darkishRed ) } } }

I don't know if this is any help to you, but 2003332927 is 'who?', or kCMIOHardwareUnknownPropertyError. In case you don't know, you can paste the number into the calculator app on macOS, use cmd-3 to display the programmers calculator and clock the little ASCII button. Are you using AudioObjectHasProperty before calling AudioUnitSetProperty?

I see from the tooltip in the last screenshot that your documents are in the cloud. You said you "moved to new computer". Did the system have time to sync all your documents? Did you try deleting the derived data folder, then archiving and distributing your app again?

all the documentation for development of applications for iOS, watchOS, iPadOS, macOS, visionOS is available without a paid developer account. To develop accessories under the MFi program, you need an MFi program membership. https://mfi.apple.com Is there anything specific you cannot find?