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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Make sure you support Dynamic Type up to the largest text size available. Take into account that there are five extra accessibility sizes available from the Accessibility Settings. It can make a huge difference for lots of users.
If you want to keep yourself up to date with what’s going on, or what has been published lately, on how to develop more accessible mobile apps, make sure you subscribe to Accessible Mobile Apps Weekly by @RobinKanatzar from @accessible_apps.
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
