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.
Obsidian is a note-taking app that lets you create a personal knowledge graph with ease. It is designed for non-linear thinking and allows you to easily link your notes together wiki-style.
Web-based note-taking tool with sync, multimedia support, real-time collaboration, checklist creation, cloud integration, AI-powered features, handwriting, and mobile compatibility.
Open source note-taking app with Markdown support, to-do integration, and synchronization with cloud services like Dropbox and OneDrive.
An end-to-end encrypted note-taking by Proton. Offline access, unlimited sync across devices, tagging, passcode and biometric security, plus advanced premium privacy features.
Multifunctional cross-device tool captures ideas, lists, voice/photo notes. Features color coding, geo-fencing, checklists, and cloud sync.
Free, open-source note-taking with rich text, cross-platform support, syntax highlighting, embedded files, and customizable interface.
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.
