Spine - Spine is 2D animation software designed specifically for software and game development.
CKEditor - Real-time collaborative future-ready rich text editor
Synfig Studio - Just another WordPress site
Summernote - Summernote is a JavaScript library that helps users create WYSIWYG editors online.
DragonBones - DragonBones is an open source project for 2D skeletal animation.
Froala Editor - Froala Editor is a WYSIWYG HTML editor that enables rich text editing capabilities for the applications.