Supabase

Supabase is a backend-as-a-service built around a hosted Postgres database, with authentication, file storage, edge functions and realtime subscriptions alongside it. React Native apps use the same @supabase/supabase-js client as web apps, which is pure JavaScript and works in Expo Go.

The React Native-specific part is setting up the client. On the web it stores the session in localStorage; on a phone you must give it storage and turn off URL session detection:

import { createClient } from '@supabase/supabase-js';
import AsyncStorage from '@react-native-async-storage/async-storage';

export const supabase = createClient(SUPABASE_URL, SUPABASE_PUBLIC_KEY, {
  auth: {
    storage: AsyncStorage,
    persistSession: true,
    autoRefreshToken: true,
    detectSessionInUrl: false,
  },
});

Supabase’s guides also recommend calling supabase.auth.startAutoRefresh() when AppState becomes active and stopAutoRefresh() when it goes to the background, because timers do not run reliably in a suspended app. Teams that want the session encrypted swap AsyncStorage for an adapter built on secure storage.

Why teams choose it: data is relational and queryable with SQL, the platform is open source and self-hostable, and Postgres row-level security lets the app query the database directly without a custom API.

That last point is also the biggest gotcha. The public key in your app is extractable by anyone, so row-level security is not optional. A table without RLS policies is readable and writable by anyone holding that key. The service-role (secret) key bypasses RLS entirely and must never appear in app code; keep it on a server. See API keys in mobile apps.

Realtime features run over a WebSocket, so expect to resubscribe after the app returns from the background. Compared with Firebase, Supabase is relational rather than document-based. See the Supabase docs.