Animo.js - Animo.js is a lightweight, open-source tool that enables developers to manipulate animations and transitions.
Ceaser - Ceaser is a handy CSS Easing Animation tool for creating any ease imaginable.
Anime.js - Lightweight JavaScript animation library
Pixi.js - Fast lightweight 2D library that works across all devices
Stylie - Stylie is an open-source, easy-to-use tool based on Rekapi that allows you to build complex web animations in a short time.
Substance - A JavaScript library for web-based content editing