When using VoiceOver on a device without a home button it can first be confusing how you can do a few things, including going to Home from an app, or opening the App Switcher, Control Center, or Notifications. Here's a quick guide for you.

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It can help to alert the user of something that happened, in a part of the screen that is not currently on focus, and that is not important enough to disrupt the user by moving VoiceOver’s focus to a different place. It can be useful to announce certain messages like errors or long running tasks that have finished (i.e. a download that finished) or with custom notifications and snack bars.

You don't have to offer an alternative layout just for the accessibility category. You can actually compare content size categories. So you could tweak the UI already for anything equal to or larger than .extraExtraLarge, for example.

You can add an observer to listen for changes in the content size category, in case it is more convenient than overriding traitCollectionDidChange(_:).