The Apple UI Design Resources section of their Human Interface Guidelines has come a long way. It used to be that you needed to use 3rd party templates in *cough* Photoshop to create visual designs for iOS apps.

Now here we are, able to simply download templates, and other preconfigured UI elements in Sketch format directly from Apple for iOS 11, watchOS and CareKit.

apple-ios11-sketch-ui-kit

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