Design Principles - An open source repository of design principles and methods
Lottie by Airbnb - Easily add high-quality animation to any native app
Facebook Design Resources - A collection of free resources made by designers at Facebook
Marionette Studio - Marionette Studio is an online animation software for beginners and professionals. Animate 2D characters and environments in minutes with no prior skills.
Facebook - Connect with friends, family and other people you know. Share photos and videos, send messages and get updates.
Spirit - The animation tool for the web.