Cloud Firestore is a NoSQL document-based database built for mobile and web app development. It does the same things Firebase does:
- Allows you to access data directly in the client - serverless
- The accessed data is updated realtime
- Makes it easy to build offline experiences
Realtime DB -> Sync app state in realtime with low latency
Firestore addresses the following firebase issues:
- RTDB can't query over multiple properties. This is typically handled by duplicating data or filtering in client.
- RTDB does not scale automatically. Cloud Firestore does.