Updated June 2017 for iOS 11.0 beta

“The Apple UI Design Resources include Photoshop and Sketch templates, and other UI materials for quickly designing iOS apps. The included resources are comprehensive and accurately depict the full range of UIKit controls, views and glyphs available to developers using the iOS SDK. They make it easier to understand how iOS apps are constructed and how to design apps that match the iOS design language. Included icon and glyph production files have been preconfigured to automate asset production using Sketch slices or Adobe Generator for Photoshop CC…”

Apple UI Design Resources for Sketch and Photoshop