Check isReduceTransparencyEnabled to lower transparency. A great example is Spotlight. Not only transparency is removed but it keeps the main color of the background, it feels personalized and contextual but reduces noise and improves contrast.
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Touch target sizes are recommended to be at least 44 x 44 points. Buttons in the navigation bar ( especially when not using nav bar button items), dismiss buttons, and custom toolbars, are use cases that tend to have smaller sizes.
When configuring a largeContentImage or adjustsImageSizeForAccessibilityContentSizeCategory, it is important to use a pdf asset and preserve the vector data so the icons are crisp at any size.
