Anima App - Design, get feedback, convert to code, publish, iterate.
Nawvel - Nawvel is a handy-dandy library of tried, tested & curated resources.
Sketch Repo - Collection of resources for anyone who uses Sketch
Google Design Sprint Starter Kit - This Kit helps you to run your first Google Design Sprint.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Design Files - Professional resources for digital designers