Colla
A shared PDF study room for two readers with independent navigation, partner awareness, cursor streaming, and rejoining.
Technology stack
React / TypeScript / React Router / PDF.js / Go / Firestore / Cloudinary
A shared PDF study room for two readers with independent navigation, partner awareness, cursor streaming, and rejoining.
The current Go room replaces the legacy Express service. Optional paid room retention is separate from the basic reading experience.
Capabilities
- PDF upload and one-partner invitation
- Independent pages and Jump to Partner
- Live presence and temporary cursors
- Theme, zoom, backgrounds, and layout
- Invitation and rejoin flows
Behind this project
Notes, Colla, and Planny: Building Apps for Writing and Studying
Explore real study workflows alongside collaborative document state, separate cursor and presence updates, and the boundary between private notes and public schedules.