Joplin
Joplin - an open source note taking and to-do application with synchronization capabilities for Windows, macOS, Linux, Android and iOS
Vikunja
The open-source to-do app. Organize everything, on all platforms.
Cryptgeon
Cryptgeon is a secure, open-source note / file-sharing service inspired by PrivNote written in rust & svelte.
HedgeDoc
HedgeDoc is an open-source, web-based, self-hosted, collaborative markdown editor
Etherpad
Etherpad is a highly customizable open source online editor providing collaborative editing in really real-time.
Trilium
Trilium Notes is a hierarchical note taking application with focus on building large personal knowledge bases.
Affine
More than Notion and Miro's next-generation knowledge base, AFFiNE unifies planning, sorting, and creation.
Memos
A lightweight, self-hosted memo hub. Open Source and Free forever.
Flatnotes
A self-hosted, database-less note-taking web app that utilizes a flat folder of markdown files for storage.
Huly
All-in-One Project Management Platform (alternative to Linear, Jira, Slack, Notion, Motion)