Firestore – Google Cloud’s NoSQL database service.

Google Cloud Firestore is a flexible, scalable NoSQL database for mobile, web, and server development. It offers real-time listeners, offline support, and automatic multi-region replication. The service includes strong consistency guarantees, atomic transactions, and sophisticated querying capabilities. Firestore provides automatic scaling, built-in security rules, and seamless integration with Firebase. It supports both native and REST APIs and includes features for data validation and transformation.