Do you have a fancy custom loading animation instead of an UIActivityIndicatorView? You may want to check if it has an accessibility label so a VoiceOver user knows that something is happening. Something like "In progress" or "Loading" could work.
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Buttons with a title, use it as its default accessibility label. Most cases, that's just perfect. But there's a few times that you might want to tweak it. Maybe the image is part of what the button does, or the text in the title is not very clear.

The .selected accessibility trait indicates when an element has been selected. You’ll notice that VoiceOver announces “selected” before the accessibility label. You can find that in the system for the selected tab in the tab bar, for example.
Guidelines from Apple: Begin with a verb that explains the results of the action. Avoid using the imperative form of a verb because that can make it sound like a command. Don’t include the action type. Don’t include the control. https://developer.apple.com/documentation/objectivec/nsobject-swift.class/accessibilityhint
Content © Daniel Devesa Derksen-Staats on Accessibility up to 11! is licensed under CC BY 4.0. License details