VoiceOver
Also called: Screen reader, TalkBack
The screen reader built into Apple platforms, which reads each element's label, value and traits aloud.
Definition
VoiceOver users move between elements by swiping and activate them with a double tap. Apps help by giving icon-only controls labels, hiding decorative images, combining the parts of a row into one element, using real buttons rather than tap gestures, and offering secondary actions through the actions rotor. Android's equivalent is TalkBack.
In practice
A heart button with accessibilityLabel("Add to favorites") is read as "Add to favorites, button".