I am not an Apple employee, but there's a good chance most of the Apple apps you mentioned use Mac Catalyst because they were originally written for iOS with UIKit. Porting a UIKit app using Mac Catalyst is going to be faster than writing a Mac version from scratch. I don't see the advantage of using Mac Catalyst for a new SwiftUI app project. SwiftUI supports both iOS and Mac so you can share a lot of the same code and provide a native Mac experience. If you don't want to provide a native Mac experience, you can avoid Mac Catalyst, make an iOS app, and let people with Apple Silicon Macs run the iPad version. I have never used Mac Catalyst so I can't tell you how mature it is.

According to Apple's Mac Catalyst documentation, the purpose of Mac Catalyst is to create a Mac version of an iPad app. Do you have an existing iPad app that you want to port to Mac? If the answer is Yes, using Mac Catalyst will make porting easier than creating a Mac version with AppKit or SwiftUI. However, Apple Silicon Macs can run iPad apps so you can get a Mac version of the app without using Mac Catalyst. If the answer to last paragraph's question is No, you are better off creating a multi-platform SwiftUI app project to make an app that runs on iOS and Mac.

What most likely has happened is Apple made changes to the user interface in Xcode 26 and the tutorial you are following has not been updated for Xcode 26. You can file a request for Apple to update the tutorial. In Xcode choose Help > Provide Feedback to send the request. I have not gone through the tutorial so I can't tell you how to go through the tutorial in Xcode 26. I recommend taking the 100 Days of SwiftUI at Hacking with Swift. https://www.hackingwithswift.com/100/swiftui This course is geared towards beginners. Hacking with Swift also has a dedicated forum for the course (https://www.hackingwithswift.com/forums/100-days-of-swiftui) to ask questions when you run into problems with the course. The forums at Hacking with Swift are more beginner-friendly than Apple's forums.

Start by adding an exception breakpoint in Xcode. An exception breakpoint will pause your app at the point of the crash so you can see where the crash occurs in your code. In Xcode choose Debug > Breakpoints > Creation Exception Breakpoint to set an exception breakpoint. For anyone to provide further help, you have to provide more information. Some helpful information to provide includes the following: When does your app crash, at startup or when something else happens in your app? Is this an iOS or Mac app? Does your app use SwiftUI, UIKit, AppKit, or some other framework? What version of Xcode are you running? Is your app a document app or a regular app? Did you add any code recently that could cause the crash? Or did the app start crashing without you making any code changes? If the exception breakpoint points at code you wrote, provide that code. The stack trace you included doesn't have enough information for anyone to help. People here are going to need to see code to help you.

Some questions. By "SwiftUI instrumentation", do you mean profile your app in Instruments with the SwiftUI instrument? What version of Xcode are you running? What version of iOS is the device running? The new SwiftUI instrument Apple added in Xcode 26 requires iOS 26+. If your device is running an earlier version of iOS, you can't use the new SwiftUI instrument. If you can't use the new SwiftUI instrument in Xcode 26, click the Add Instrument button above the timeline pane graphs and add the legacy View Body and View Properties instruments to profile the app. Also, remove the SwiftUI instrument from the trace.

What did you do after you downloaded the xip file? The xip file is a compressed file. You have to double-click the xip file to expand the compressed file so you can run Xcode.

but the attribute inspector just does not show up, I can have the simulator open or closed I click on it nothing works. Can you provide more details about what you are trying to do that doesn't work? What do you mean by attribute inspector? You mentioned you are learning SwiftUI. The attributes inspector is used with storyboards, which SwiftUI does not use. SwiftUI uses previews to let you see how your user interface looks before you run your app. Are you trying to open the attributes inspector? Or are you trying to show the SwiftUI preview? Or are you trying to do something else?

If your sidebar has a list, you can use the .listStyle modifier to give the list a diffferent style than the sidebar style, which is the default for a navigation split view on Mac. The following modifier creates a plain list style: .listStyle(.plain) If your sidebar doesn't have a list, show the code for it so people can provide an alternative to the .background modifier you used in your example.

The imported type identifier needs to conform to one of the base types. Apple has a list of system-defined UTTypes at the following link: https://developer.apple.com/documentation/uniformtypeidentifiers/system-declared-uniform-type-identifiers I'm not sure what UTType would open any file but you could test the following: public.item public.content public.data public.text

You might find the following article helpful: https://marioaguzman.wordpress.com/2020/09/12/auth/

First, open your repo in another git app, such as SourceTree, and see if the other app shows the numerous changes. That will let you know whether your problem is an Xcode problem or a git problem. You can remove the git repository and see if that fixes the problem. In the Finder, press Cmd-Shift-Dot to show hidden folders. The git repository is in a .git folder inside the playground folder. You will have to create a new git repository for the playground after removing the old git repo. You should also add a .gitignore file to your git repository to ignore system files. An easy way to create a git ignore file is to go to the following URL: https://www.toptal.com/developers/gitignore/ Enter Xcode in the search field and click the Create button to create a git ignore file. Create a plain text file for the git ignore file and paste the contents of the git ignore file that you generated into the text file.

I don't know of any way to create UIKit controls with XML-like strings. In UIKit you can create the UI visually using a storyboard or create the UI in code.

Do you have a storyboard or xib file open in your project? The attributes inspector works with storyboard and xib files. You have to open a storyboard or xib file to have access to the attributes inspector. If you select a source code file in the project, the attributes inspector won't be available. You can access the inspectors by choosing View > Inspectors.

Archiving the project by choosing Product > Archive creates a binary with both Apple Silicon and Intel architectures for me on macOS 15.

I'm not sure if you are asking about running a playground on an iPhone or if you are asking about running an app you wrote with the Mac version of Swift Playgrounds on an iPhone. But the answer is the same either way. No, you won't be able to run your code on an iPhone. Swift Playgrounds is available for iPad and Mac, not iPhone. You are not going to be able to run playground code that is not an app on an iPhone. You could run the code on an iPad if you install the iPad version of Swift Playgrounds. The Mac version of Swift Playgrounds makes Mac Catalyst apps, a Mac version of an iPad app. You are not going to be able to run an app you make with the Mac version of Swift Playgrounds on an iPhone. My suggestion is to continue learning to code using Swift Playgrounds on Mac. When you are ready to make an iPhone app, create an iOS app project in Xcode.