Joplin

Joplin is an open-source note-taking and to-do application that can handle a large number of notes organized into notebooks. The notes are in Markdown format and can be synchronized across multiple platforms using various cloud services, including Dropbox, OneDrive, and Nextcloud. Joplin supports rich text, attachments, and has a web clipper for saving web pages, making it a versatile tool for managing personal and professional data.