Sprite.js is a framework for creating animations and games using sprites that works across desktop and mobile browsers. Crafty.js is a lightweight modular game engine that includes components like animation, collision detection, and sprites. Sprite.js focuses on animation but lacks some features, while Crafty.js is a full-featured engine that lacks physics support. Both support 2D, parallel and isometric views but Crafty.js has more features and support for audio and multiple graphics.