Excalidraw

Spacedeck is a self-hosted real-time collaborative whiteboard application with rich media support. Use Spacedeck for mood boards, collages, as a collaborative digital whiteboard, or design thinking.

WBO is an open-source online collaborative whiteboard that allows many users to draw simultaneously on a large virtual board.

OpenBoard is an open-source, cross-platform teaching software for interactive whiteboards designed primarily for use in schools and universities.

InVision is an online whiteboard and productivity platform that gives you clarity, collaboration, and control of everything you need to power your design process.

Stormboard is a collaborative whiteboard app that helps teams capture and organize ideas, prioritize tasks, plan projects, and manage meetings.

Web Whiteboard by Miro is a friendly online whiteboard app for any business or educational institution that makes drawing, collaboration, and sharing easy.