What is the ideal distance between labels? It depends on styles for both of them and the dynamic type size, right? You wouldn't want to have the same distance for small and large text sizes. We can configure a standard distance between baselines.
You may also find interesting...
It is possible to use custom fonts and for them to still work great with Dynamic Type. You need to define the default size and use UIFontMetrics to get the scaled font for each one of the styles you'd like to use. https://developer.apple.com/documentation/uikit/uifontmetrics/scaledfont(for:)
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.
Sometimes we may fail to convey to the user of things changing on the screen in a perceivable way. Toasts and similar should be announced. We may want to make clear that some content on the screen changed. Or we might want to update on progress.
