This is a strange one. You might try setting up something like Sentry to catch these errors and hopefully give you more info about what’s going wrong.
One issue you might face is that Apple might reject your app if it is based on SDK 34 because it contains code that references UIWebView which Apple has deprecated. This was fixed in SDK 36 (if an app is built with SDK 36 I believe it would just have to be rebuilt to take advantage of the fix.
@wodin This app is currently in app store and was accepted by Apple. More over we see this with only a few iOS users. Most users are able to seamlessly download the app and work with it.
this type of error happens when your js code throws an error before being able to render the app root component, so there are basically an infinite number of reasons why you may be seeing it! it’s really impossible to guess
as @wodin suggested, if you use an error reporting service like sentry you can see the exact error that is leading to this.