iOS Design Course - The Complete iOS Design Course with Sketch from Bitfountain
iOS 12 GUI - Free collection of UI components and screens of iOS 12
Xcode - Xcode is Apple’s powerful integrated development environment for creating great apps for Mac, iPhone, and iPad. Xcode 4 includes the Xcode IDE, instruments, iOS Simulator, and the latest Mac OS X and iOS SDKs.
Fludish Sketch UI Kit - 🌱 Fluent iOS UI Kit designed for Sketch.
draw.io - Online diagramming application
Velvet UI Kit - Cozy iOS UI Kit designed for Sketch 🌸