Supabase vs Firebase for a React Native App in 2026

Supabase and Firebase both promise the same thing to a small team: skip building a backend and ship the app. Auth, database, file storage, functions and realtime come ready-made. The difference is underneath: Firebase is built around Google's NoSQL Firestore, while Supabase is built on PostgreSQL. That single choice shapes how you model data, write permissions, query, and eventually grow or migrate.

This guide compares Supabase vs Firebase for a React Native app in 2026: data model, auth, security, realtime, functions, pricing behaviour and lock-in, with a recommendation for common app types.

Key takeaways

• Supabase is PostgreSQL with auth, storage, realtime and edge functions on top; security is enforced with row-level security.
• Firebase centres on Firestore (a document database) with auth, storage, functions and Google's broader tooling (Crashlytics, Remote Config, Analytics, FCM).
• Relational data (bookings, orders, multi-tenant SaaS) fits Supabase's Postgres more naturally; document-shaped, real-time data fits Firestore well.
• Migration paths differ: Supabase's standard Postgres makes moving to your own backend easier later.
• You can mix: many apps use Firebase for push or crash reporting with another backend.

The comparison

Data model: the real decision

Firestore stores documents in collections. It's excellent for data read in the same shape it's written (a chat thread, a user's feed) and for live listeners. Relationships require denormalisation (copying data into several documents) and careful design to avoid many reads.

Supabase gives you relational tables, foreign keys, joins and transactions. Data like "classes, bookings, memberships, payments across many gyms" fits naturally, and reporting is just SQL.

If your data has many relationships and you'll need reports, Postgres usually wins. If your data is mostly self-contained documents with lots of live updates, Firestore is a good fit.

Security: rules vs row-level security

Both let the app talk to the database directly, which means security can't live in the app:

• Firebase Security Rules define who can read and write which documents, evaluated on Google's servers.
• Supabase uses PostgreSQL row-level security policies, so the database itself filters rows per user.

In both cases, missing or loose rules are the most common serious mistake. Write them first, test them with a second account, and keep sensitive operations (payments, admin actions) in server-side functions.

From the field: I've built on Supabase, Firebase and custom backends: Supabase and PostgreSQL are in my core data stack, and Firebase appears in my mobile tooling. For multi-tenant products like Floey I'd always reach for PostgreSQL, because tenant isolation, reporting and relational data are where Postgres is strongest.

Auth in a React Native app

Both platforms handle sign-in well from React Native, with a few setup details:

• Session storage: give the client a storage adapter so sessions survive restarts, and keep tokens in secure storage where possible.
• Social sign-in: OAuth flows open a browser and return to the app through a deep link, so configure your URL scheme and redirect URLs carefully.
• Native SDKs vs JavaScript SDKs: Firebase has native React Native libraries with features like Crashlytics and FCM; Supabase's JavaScript client works across Expo and bare apps.
• Sign in with Apple: if you offer other social logins on iOS, Apple expects an equivalent privacy-friendly option, and both platforms support Sign in with Apple.

Pricing behaviour

Both have free tiers and charge as you grow, but they scale differently:

• Firebase charges largely per document read, write and delete, so data model design directly affects cost. A screen that reads 500 documents per open gets expensive at scale.
• Supabase prices by plan with compute, storage and usage limits, which tends to be more predictable for relational workloads.

Model your expected reads and writes for your busiest screens before committing, and set budget alerts on either. A rough spreadsheet of daily active users times reads per session catches most surprises before they reach an invoice.

Lock-in and growing up

Neither choice is permanent, but the exit costs differ:

• Leaving Supabase: your data is standard PostgreSQL, so you can move to a managed Postgres and build your own API gradually.
• Leaving Firebase: moving from Firestore to a relational database means remodelling data and rewriting queries and security logic.

If you expect to build your own backend eventually (complex business rules, integrations, multi-tenancy), starting on Postgres makes that step smaller.

Recommendations

Firebase in an Expo app

There are two ways to use Firebase with React Native. The Firebase JavaScript SDK works in Expo Go for services such as Firestore and Authentication, but not for native-only services like Crashlytics or Performance Monitoring. React Native Firebase (@react-native-firebase/*) wraps the native SDKs, covers those services, and works in Expo through config plugins and a development build. If you need crash reporting, performance traces or Firebase's push integration, use React Native Firebase.

FAQ

Is Supabase better than Firebase?

For relational data, reporting and an easier path to your own backend, Supabase is usually better, because it's PostgreSQL underneath. Firebase is excellent for document-shaped, real-time data and comes with Google's wider app tooling. The right choice depends on your data model.

Can I use Supabase with React Native and Expo?

Yes. The Supabase JavaScript client works in React Native and Expo; you provide a storage adapter (for example secure storage or AsyncStorage) for the auth session, and use deep links for OAuth sign-in flows.

Is Firebase free for small apps?

Firebase has a free tier that covers many small apps and prototypes. Costs grow with document reads and writes, storage, functions and bandwidth, so design your data model to minimise reads and set budget alerts as you grow.

Can I use Firebase and Supabase together?

Yes. A common pattern is Supabase for the database and auth, with Firebase Cloud Messaging for push notifications, Crashlytics for crash reporting, or Remote Config for feature flags.

Next steps

If you're choosing a backend for a React Native app, or outgrowing the one you started with, I can recommend the right foundation and plan the move if one is needed. Get in touch, or see how I work as a full-stack developer.

Sources

• Supabase documentation, Supabase
• Supabase with Expo React Native, Supabase
• Firebase Security Rules, Firebase
• Cloud Firestore data model, Firebase
• Row security policies, PostgreSQL docs