Whether it's bookmarks or passwords, files or shopping lists...Turtl organizes it all and makes it easy to find later. Sync across your devices. Leave nothing behind.
Zim brings the concept of a wiki to your desktop. Store information, link pages and edit with WYSISYG markup or directly typing some lightweight markup syntax and see it previewed as-you-type. Creating a new page is easy by either clicking on the "Create new note"...
Cross-platform app for creating and organizing notes from text, web pages, images, and voice memos. Offers security features and integrates with various tools.
Plain text notepad with markdown support and todo list manager for Linux, Mac OS X and Windows, that works together with the notes application of ownCloud.
Multifunctional cross-device tool captures ideas, lists, voice/photo notes. Features color coding, geo-fencing, checklists, and cloud sync.
Made by the company behind 
WordPress, Simplenote enables users to take notes, lists, and ideas. These notes are stored on the cloud and are accessible across multiple devices.
TiddlyWiki is a single html file with all the characteristics of a wiki - including all of the functionality (including editing, saving, tagging and searching) and the style sheet. Because its a single file, its very portable - you can email it, put it on a web server or share...
Streamline teamwork with real-time collaboration, drag-and-drop content organization, and visual simplicity across notes, tasks, wikis, and databases.
Open source note-taking app with Markdown support, to-do integration, and synchronization with cloud services like Dropbox and OneDrive.
HedgeDoc (fcommunity-driven fork of CodiMD) is an open-source collaborative markdown editor. With HedgeDoc you can easily collaborate on notes, graphs and even presentations in real-time. All you need to do is to share your note-link to your co-workers, and they’re ready to go.
