UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
iOS 12 GUI - Free collection of UI components and screens of iOS 12
Moqups - The most stunning HTML5 app for creating resolution-independent SVG mockups, wireframes & interactive prototypes for your next project
Fludish Sketch UI Kit - 🌱 Fluent iOS UI Kit designed for Sketch.
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
Landing UI Kit - Handcrafted UI components for landing pages