A quick way for turning on, or off, VoiceOver is by using Siri. Say something like: "Hey, Siri! Turn on VoiceOver", and you'll find yourself using VoiceOver in no time. You can also do the same with other technologies like Voice Control.

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Attributed accessibility labels are a thing! They'll let you specify (for the whole accessibility label or a portion of it) VoiceOver's language, to read punctuation marks, spell it out, correct the pronunciation, or even change the pitch. @RobRWAPP has a very detailed blog post explaining each one of these attributes: https://mobilea11y.com/blog/attributed-accessibility-labels/ And here's Apple's official documentation for them: https://developer.apple.com/documentation/uikit/speech-attributes-for-attributed-strings

Custom actions work with VoiceOver, Switch Control and Full Keyboard Access. They also do for Voice Control. You can say "Show actions for <item name/number>", and an action sheet with all options, numbered, will be presented to the user. For some use-cases, Voice Control users might not feel it is a big win. Navigation is not as big of an issue, and interacting with custom actions might be a bit trickier than with "exposed" buttons. But lots of times seems a fair compromise.

If you need to send announcement notifications that can step into each other, they will by default, interrupt ongoing announcements. But you can pass attributed strings as parameters too, letting you specify announcements to be queued.