There are a ton of customisation options in the accessibility settings in iOS. When doing things the Apple way, this options should, in most cases, just work for you. If not, you can find flags to check for all these options in UIAccessibility.

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In iOS' Settings you can specify your preference to use bold text. This can be checked in code in a couple ways: 1. isBoldTextEnabled in UIAccessibility: https://developer.apple.com/documentation/uikit/uiaccessibility/isboldtextenabled 2. legibilityWeight from UITraitCollection: https://developer.apple.com/documentation/uikit/uitraitcollection/legibilityweight
UINotificationFeedbackGenerator has a “success” feedback type. Consider using it when a task was performed successfully together with any other visuals or sound. The use of multiple modes just makes it easier for everyone to understand your app.

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.