If you use Color Sets in the Assets Catalog to define your color palette, make sure you enable variants for the Any, Light and Dark appearances and also High Contrast. You'll be able to define variations of the color that have better contrast.

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You can enable the possibility of providing assets for different appearances including light/dark modes and high contrast. As we've seen, that's valid for colors, but you can do the same for images too! https://x.com/dadederk/status/1594724075590619138?s=20&t=XJrlJiGSCTR9sJC7XPZPjA

When implementing a UISlider, it is a good idea to consider how much the slider value should change when swiping up/down to adjust it. It might not always make sense to do it in 10% increments, which is the default behaviour. Could be because the value at those intervals doesn't make sense, or feel random, or because it wouldn't provide the user with a fine enough control being able to go through the whole slider in just 10 swipes. It user will still be able to adjust the slider to any value by double tapping and holding and then moving the finger left or right, bypassing VoiceOver gestures. VoiceOver announces the new value as it changes.

Configuring the header accessibility trait, when appropriate, is one of my favourite accessibility quick wins. In this example, you need a single swipe down, instead of 12 swipes to the right to get to from Podcasts to Artists, in the app.