Did you use Xcode's search on the project? Did you use Finder set to show invisibles and search the project folder? Until you minesweep, I'd take the error at face value. If you are certain there is only one instance, you may need to either file a bug against the backend and see what comes back, and/or submit a project that demos the issue to DTS and burn a support ticket to have them take a look. Good luck.

then it disappears. This is a daily FAQ - search here on: builds disappear ...and know that it is usually a matter of just being patient while the backend catches up with itself. Good luck.

Your app only knows about itself. The user's reading habits are considered private. If, however, you're dealing w/managed devices, see this doc on info that is available: https://developer.apple.com/documentation/devicemanagement/app_and_book_management/service_configuration/getting_app_and_book_information

Show some code

That line is empty... Show some code.

Good on you for including them, but nothing jumps out at me in those logs, sorry. we have tested on test devices and emulators and the app works fine, in app center I get the following log In that example, you might want to see Eskimo's reply/advice on debug vs. release builds in this previous thread: https://developer.apple.com/forums/thread/69035

It's a blackbox, but I see the same, and I'm going to say yes, homebrewed in the belly of the mothership. I'm sure an intern is proud, none the less. If that's an issue, try goggle, instead, where searching on: apple dev forums xcode source control results in 'About 638,000 results...' About using the forums 'ever', and hearing tales, keep in mind that until the current version rolled out here just a few months ago, devForums were run on a package from JIVE Software. What you see now is entirely different, and I suspect hasn't been around long enough to be part of the 'tales' surrounding that long running hot mess, which had been in place in slightly different versions, for several years.  In the end, I think it all comes down to how good your search fu is. I'm still honing mine with the new forums, so where I used Google in the past, I'm using it more now. Don't get me started on the excuse for a search engine tied to the magnifying glass above right...

If you only have 8GB ram, add more. If you have less than 75GB free space on your SSD, find more. If you know how to locate and delete xcode prefs in ~/Library/Preferences, see if that helps. Restart the machine, create a new sample app, your choice of template, then try to add more devices. Might also try housecleaning Keychain Access. Otherwise, it and your macOS are betas, crashes come w/territory, so... File bugs, cross fingers and wait to see if the next betas fare better. Good luck.

Given the inherent limitations in relation to opening one app from another, I'm not sure via a context menu is workable. See: https://developer.apple.com/forums/thread/83477

Not sure it's your problem, but the latest beta release notes say this... SwiftUI ...Known Issues ......ProgressView generic type signature has changed, adding the ProgressViewStyleConfiguration.CurrentValueLabel generic parameter. This change does not require any source changes, but will cause apps you compile using an earlier beta SDK to quit unexpectedly. (63580200) You might want to file bugs and wait for next beta/release.

Look at that zip in the Finder, being sure that the option to show extension is enabled. You may find something such as: myApp.zip.ipa

do it from the code by comparing it with the existing version and to notify the user. Find a way to get that done, it's the only overall reasonable solution in your example, there are no other workable options outside of abandoning the current app and user pool, ouch.

Unless you're attempting to submit to testflight and not the store, you should know that devs are obligated to use only release tools/SDKs/OSs when submitting to the store. That means to avoid Xcode 12 beta, iOS 14 beta, macOS beta, etc. for now. Good luck.

You may want to use the contact us link below to make this request to support directly. Good luck.

I have never seen such behavior.  Others have, often, so this isn't unique to you. Be patient while the backend catches up. In the mean time, feel free to search here on: build disappears - https://developer.apple.com/forums/search/?q=build%20disappears