PSD to Sketch Design Converter - Convert a Photoshop design to a layered Sketch file for free
Symbol Design System - Advanced web-design system based on Sketch nested symbols.
Zeplin - Collaboration app for UI designers & frontend developers
Supernova Studio - The world’s first true design-to-code platform 🚀
Sketch Repo - Collection of resources for anyone who uses Sketch
Confetti for Adobe XD - Generate gorgeous confetti patterns in 1 click