Source Wireframe Kit - Library of 537 blocks for desktop and mobile prototyping
Contra Wireframe Kit - Open source wireframe kit for design and prototyping 🚀
UX Wireframe Kits - Simple, beautiful wireframe kits for Sketch & Illustrator
Platforma - Wireframe library of layouts and UI elements
UI Flow Cards - Construct web pages with ease, using cards
Platforma for iOS - The ultimate wireframe kit for app prototyping