Lottie by Airbnb - Easily add high-quality animation to any native app
Marionette Studio - Marionette Studio is an online animation software for beginners and professionals. Animate 2D characters and environments in minutes with no prior skills.
Spirit - The animation tool for the web.
Animaticons - Beautiful, customizable animated GIF icons.
Jitter - A simple animation tool on the web
CSS Animation Cheat Sheet - Awesome CSS3 plugin for spiffy animations