Supabase vs Firebase:
Which Backend for Your Mobile App?
Supabase is an open-source backend on Postgres. Firebase is Google's backend, built around the Firestore document database. Both give a mobile app sign-in, a database, file storage and realtime updates. This page compares them on the points that matter for an iPhone or Android app, from data model to offline mode.
Is Supabase or Firebase better for a mobile app?
Choose Supabase when your data has relations and you want SQL, one access-rule language and an open-source backend. Choose Firebase when the app must work offline, you want built-in push through Firebase Cloud Messaging, or you already live in Google tools. Fastshot connects Supabase natively, with email, Google and Apple sign-in, a database and image storage.
Last updated: November 4, 2026
Supabase vs Firebase: The Backend of a Mobile App
Checked against both vendors' documentation in November 2026.
| Question for a mobile app | Supabase | Firebase |
|---|---|---|
| Data model | Postgres tables with foreign keys, joins and SQL | Cloud Firestore keeps documents in collections, with no tables or rows. The Realtime Database stores one JSON tree |
| Relational data | Native: orders, items and users link through keys and come back in one query | Denormalize your documents or query twice. Firebase SQL Connect, formerly Data Connect, adds a managed PostgreSQL on Cloud SQL behind GraphQL |
| Sign-in methods | Password, magic link, one-time password, social sign-in including Apple, Google, Facebook and Microsoft, and SSO | Email and password, phone, Google, Facebook, Twitter, GitHub, Apple, anonymous and custom. SAML and OpenID Connect need the Identity Platform upgrade |
| Realtime updates | Realtime service with Broadcast, Presence and Postgres Changes | Snapshot listeners on Firestore documents and queries, and a Realtime Database that syncs JSON to every client |
| File and image storage | S3-compatible storage with resumable uploads, a CDN and on-the-fly image transforms, guarded by the same policies as your tables | Cloud Storage for Firebase, built on Google Cloud Storage and guarded by Security Rules |
| Offline mode | No offline cache in the client. Supabase's own comparison says offline access needs your own caching strategy | Firestore caches the data your app uses and syncs writes when the device reconnects. On by default in the Android and Apple SDKs |
| Access rules | Row level security: SQL policies on each table, enforced inside the database | Security Rules: a separate rules language for Firestore and Storage. Server client libraries bypass them |
| Push notifications | No built-in push product. Supabase documents sending Expo or Firebase Cloud Messaging pushes from edge functions | Firebase Cloud Messaging for iOS, Android and web, with a payload of up to 4096 bytes |
| Server code | Edge Functions in TypeScript on Deno | Cloud Functions in JavaScript and TypeScript, and Python in the second generation |
| Expo and React Native | supabase-js works in an Expo app, and the docs include an Expo quickstart | The Firebase JS SDK covers Auth, Firestore, Realtime Database and Storage in Expo Go. React Native Firebase needs custom native code and cannot run in Expo Go |
| Hosting and openness | Open source, and you can self-host it | Managed by Google, with open-source client SDKs |
Pick Supabase If Your Data Has Relations
Most apps end up relational. A booking app links users to appointments to services, a store links customers to orders to items. In Supabase those links are foreign keys and joins, and a screen can get everything it needs from one query. In Firestore you copy fields between documents or run several reads, and you keep the copies in sync.
Supabase also keeps access control in one place. A row level security policy is a SQL rule attached to a table, and the database enforces it for every client. Supabase's own docs warn that a table in an exposed schema without row level security can be read and written by any role with a grant, so you enable it on every table. Because the stack is Postgres and open source, you can move or self-host later.
Pick Firebase If Offline and Push Matter Most
Firebase is the stronger fit when an app has to keep working with no signal. Firestore's Android and Apple SDKs cache the data your app uses, let people read and write while offline, and sync the changes on reconnect, with last write winning when the same document changed twice. Supabase has no equivalent built into its client.
Firebase also bundles things a mobile team often wants next to the database. Firebase Cloud Messaging sends push notifications to iOS and Android, Analytics and Crashlytics belong to the same platform, and the document model is quick to start with when the data is simple. The cost is the document structure itself, which gets awkward as relations grow.
Which One Fits an Expo or React Native App?
Both work in Expo, with different catches. Supabase uses one JavaScript client, supabase-js, so it runs in Expo Go and in a store build alike. Firebase offers two routes: the JS SDK runs in Expo Go but leaves out Analytics and Crashlytics, while React Native Firebase wraps the native SDKs, needs a development build and cannot run in Expo Go.
Three questions settle most choices. Does the app need to work offline? Is the data relational? Do you want push from the same vendor? Offline and push point to Firebase. Relations and SQL point to Supabase. For a first version without those needs, Supabase is the simpler setup, and it is the one that plugs straight into Supabase with React Native.
Where Fastshot Fits With Supabase Built In
Fastshot connects Supabase natively. When your app needs accounts, saved data or uploads, the AI shows a connect widget in the chat, you tap connect, and the app gets sign-in with email, Google and Apple, a Postgres database with realtime subscriptions, and image storage. You describe features in plain language, such as saving profiles or adding photo attachments, and Fastshot writes the screens, queries and table structures.
No backend yet? Skip the prompt and the app stores data locally, then connect Supabase whenever you are ready. The walkthrough is in add a backend to your app, and the AI app builder page shows the whole path to the App Store and Google Play.
The Same Rule in Supabase and Firebase
Each person can read and change only their own rows or documents. First, a Supabase row level security policy.
alter table todos enable row level security;
create policy "Individuals can view their own todos."
on todos for select
to authenticated
using ( (select auth.uid()) = user_id );And the equivalent idea in Firestore Security Rules, which use their own syntax and are deployed separately from the data.
rules_version = '2';
service cloud.firestore {
match /databases/{database}/documents {
match /users/{userId} {
allow read, create, update, delete: if request.auth != null && request.auth.uid == userId;
}
}
}What a Supabase Backend Gives a Fastshot App
The three pieces Fastshot wires up once Supabase is connected.
Accounts
Ask for a login screen, Google sign-in or Apple sign-in and the AI builds the interface and connects it to Supabase Auth. Sessions are handled for you.
Database
Ask for profiles, a favorites list that persists across sessions, or live updates when new items arrive. Fastshot writes the queries, table structures and realtime subscription code.
Image storage
Ask for profile photos, post attachments or receipt pictures. Files go to Supabase Storage buckets with access policies, and each file gets a public URL.
Frequently Asked Questions
Which is best, Supabase or Firebase?
Neither wins everywhere. Supabase fits relational data, SQL and an open-source stack, and Firebase fits offline-first apps, built-in push and Google tooling. For a first mobile app with users, saved records and photo uploads, Supabase is usually the quicker setup.
Why is everyone using Supabase?
It puts auth, a Postgres database, storage, realtime and functions behind one client, and Postgres is a database many developers already know. AI app builders helped: the built-in backend in Lovable runs on Supabase's open-source foundation, Bolt offers it, and Fastshot connects it natively.
What are the pros and cons of Supabase?
The pros are SQL, joins, row level security, realtime, open source and a self-hosting option. The cons for mobile are no built-in offline cache and no built-in push product, and row level security must be switched on and written for every table, because an exposed table without it is open to any role with a grant.
Why is Google shutting down Firebase Studio?
Google has not given a reason in its notice. It says Firebase Studio sunsets on March 22, 2027, new workspaces and signups ended on June 22, 2026, and existing workspaces can move to Google AI Studio or Google Antigravity. Core Firebase products such as Firestore and Authentication are not affected.
What is cheaper, Firebase or Supabase?
Both have free tiers and charge for usage beyond them, and prices change, so use each vendor's pricing page. One structural difference is worth knowing: Firestore bills for the documents you read, write and delete plus index entries read by a query, so chatty screens and long lists show up directly on the bill.
Can I use Supabase in Fastshot without writing SQL?
Yes. You ask for features in plain language, for example saving user profiles or showing real-time updates when items are added, and Fastshot generates the table structures, queries and subscription code. You tap the connect card in the chat and Fastshot sets up the backend.
Do I need a backend for my app at all?
Not for a personal tool. Without Supabase a Fastshot app keeps data on the device with local storage, which is enough for a habit tracker or a calculator. You need a backend when people sign in, share data between devices or upload files.
What is better than Supabase for a mobile app?
For apps that must work offline, Firebase with its Android and Apple SDKs is the stronger choice, and for push it brings Firebase Cloud Messaging. For nearly everything else with accounts and relational data, Supabase is a strong default. Pair either with push notifications when you need to re-engage users.
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