CollabyDraw

Virtual whiteboard for sketching hand-drawn like diagrams

Apache ECharts is a powerful, interactive charting and data visualization library for browser

The HTML5 Creation Engine: Create beautiful digital content with the fastest, most flexible 2D WebGL renderer.

The communications platform that puts data protection first.

whiteboard SDK / infinite canvas SDK

Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..

Focalboard is an open source, self-hosted alternative to Trello, Notion, and Asana.

Zulip server and web application. Open-source team chat that helps teams stay productive and focused.

Shared data types for building collaborative software

Etherpad: A modern really-real-time collaborative document editor.