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.
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@azzoor has this great video with some advice on how to set up your device for testing accessibility and a ton of tips will get you testing effectively in no time. https://m.youtube.com/watch?v=Ca1H6wF348g&feature=youtu.be

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.
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.
Content © Daniel Devesa Derksen-Staats on Accessibility up to 11! is licensed under CC BY 4.0. License details