Firebase
Google BaaS: Firestore (NoSQL), Auth, Hosting, Cloud Functions, Storage, Realtime DB, Cloud Messaging. Direct competitor to Supabase, but NoSQL and tied to GCP.
Strengths
- Most complete BaaS stack: auth + DB + storage + push + functions in one
- Native Realtime (subscribe to changes in 1 line), historically Firebase's killer feature
- Generous Spark free tier: 1 GiB Firestore, 50k reads/day, 20k writes/day
Limitations
- Firestore is NoSQL, no SQL, no joins, different modeling
- Strong GCP vendor lock-in, migrating away = rewriting the data layer
- Costs explode quickly past free tier (read-heavy, document size)
Best for
- Mobile apps needing simple Realtime DB (chat, presence)
- Teams already on GCP wanting an aligned BaaS