When using Voice Control, say: "Show names". You'll see all the accessibility labels for interactive elements overlaid on the screen. It will help you identify labels that can be improved, or actually missing. Labels are not just for VoiceOver.
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accessibilitySpeechPitch lets you emphasise something changing VoiceOver's pitch. The value goes from 0.0 to 2.0. The default is 1.0. Twitter could change pitch to read hashtags, for example, avoiding repetition but still signalling they're there.
Sometimes, buttons change meaning, for example when toggled. An example is a play button, tap it and it becomes a pause button. In such case, updating its accessibility label will be clearer than trying to convey the change with traits or values.
Do you know when a UI element is greyed out to show that it is disabled? Yes, there is an accessibility trait for that too: .notEnabled. VoiceOver will say “dimmed” after its accessibility label and Voice Control and Switch Control will skip it.
