Invision - Prototyping and collaboration for design teams
Design Principles - An open source repository of design principles and methods
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Facebook Design Resources - A collection of free resources made by designers at Facebook
Frame.io - Video Post Production Collaboration Software
Facebook - Connect with friends, family and other people you know. Share photos and videos, send messages and get updates.