List of free note-taking tool/service for developer👇🏽

Deepnote
Deepnote is a new kind of data science notebook. Jupyter-compatible with real-time collaboration and running in the cloud.
Tag: data-science, note-taking
Unlimited personal projects (with up to 750h of Standard Hardware per month) Teams, up to 3 editors & unlimited viewers

Joplin
Joplin is a free, open source note taking and to-do application featuring search, tags, Markdown, and more. Available on Windows, macOS, Linux, Android, and iOS.
Tag: note-taking
Open Source

Gitbook
GitBook helps you publish beautiful docs and centralize your teams' knowledge. From technical teams to the whole company.
Tag: knowledge-base, note-taking, docs
Unlimited Public Spaces Unlimited Private Spaces Advanced Editing Capabilities Publish And Customise Your Docs Custom Domains

Free offer: Free bookmark manager, task manager, notes, and 500MB of files.
Notion
A new tool that blends your everyday work apps into one. It's the all-in-one workspace for you and your team.
Tag: productivity, note-taking
Free for individuals Unlimited pages & blocks Share with 5 guests Sync across devices APIBETA
evernote
Accomplish more with better notes. Evernote helps you capture ideas and find them fast.
Tag: productivity, note-taking
Sync up to 2 devices Find notes fast with search and tags Apply rich formatting to your notes Clip web pages 25MB maximum note size 60MB monthly upload limit
MindMeister
100% customizable mind map designs! Change alignments, add images, videos, etc. Invite your team, comment and vote - Try the free plan or go Pro!
Tag: productivity, note-taking
Up to 3 mind maps Real-time collaboration