iOS 12 GUI - Free collection of UI components and screens of iOS 12
Pencil Project - Single-user mockup / wireframing / diagramming tool
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 🌸
iOS Design Course - The Complete iOS Design Course with Sketch from Bitfountain