Real time sync

Clients subscribe to a document or query with onSnapshot, and Firestore pushes an update to every active listener as soon as the underlying data changes — no polling required.

• Multi-region database locations (like nam5 or eur3) replicate data across multiple regions with strong consistency for reads and writes, at the cost of somewhat higher write latency than a single-region location
• Cloud Functions can trigger on the same document write events that power client listeners, so server-side logic and connected clients react to the same change
• Firestore integrates closely with Firebase Authentication, which is what Security Rules typically use to decide who can read or write a given document

This combination — realtime listeners plus event-driven functions — is what makes Firestore a common choice for chat apps, live dashboards, and collaborative features.

Introductory overview of use cases for Firestore

1. Build collaborative apps with live updates
2. Implement chat and messaging with low latency
3. Sync user profiles across devices in real time
4. Store session state for offline-first experiences
5. Enable multi-region data availability
6. Audit user actions for security compliance

End of use cases