Scrapbox - A new style of note-taking that lets you create, discuss, and learn together in one self-organizing space.
CKEditor - Real-time collaborative future-ready rich text editor
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
TinyMCE - TinyMCE is a content editor that functions as a plug-in for Wordpress websites.
Unit Notes for iOS - A simple and powerful note-taking app.
Summernote - Summernote is a JavaScript library that helps users create WYSIWYG editors online.