The `@authdog/react-native` SDK brings Authdog to React Native and Expo apps: a provider, session and user hooks, sign-in/out helpers, and a secure-storage adapter. Sign-in uses a deep-link redirect that lands with a token. It reads the [session](/docs/concepts/sessions-tokens) Authdog issues.

## Install

```bash
npm install @authdog/react-native
npx expo install expo-secure-store
```

Requires React 18/19 and React Native `>=0.74`. There's no hard Expo dependency — `expo-secure-store` is only for persistent storage. Set `EXPO_PUBLIC_PK_AUTHDOG` to your publishable `pk_...` key.

## Wrap your app

Pass the public key and a storage adapter. Without one, sessions are held in memory and don't survive a restart, so use the SecureStore adapter in real apps:

```tsx
import * as SecureStore from "expo-secure-store"
import {
  AuthdogProvider,
  createSecureStoreAdapter,
} from "@authdog/react-native"

export default function App() {
  return (
    <AuthdogProvider
      publicKey={process.env.EXPO_PUBLIC_PK_AUTHDOG!}
      storage={createSecureStoreAdapter(SecureStore)}
    >
      <RootNavigator />
    </AuthdogProvider>
  )
}
```

## Sign in with a deep link

`useSignIn` opens the hosted flow; `useRedirectHandler` extracts and validates the token when your app is reopened via its callback URL:

```tsx
import { Linking } from "react-native"
import { useSignIn, useRedirectHandler } from "@authdog/react-native"

const { signIn } = useSignIn()
const { handleRedirect } = useRedirectHandler()

Linking.getInitialURL().then((url) => url && handleRedirect(url))
// trigger sign-in
signIn("myapp://callback")
```

## Read the session

- `useUser()` — `{ user, fetchUser, isAuthenticated, isLoading, error }`
- `useSession()` — `{ session: { token, isAuthenticated }, isLoading }`
- `useSignUp()`, `useSignOut()` — `{ signUp/signOut, isLoading, error }`
- `useAuthz({ permissionsUrl })` — `{ fetchPermissions, hasPermission }` for UI hints

`useAuthz` is for showing and hiding UI only — enforce access on your [backend](/docs/backend) with your [authorization](/docs/concepts/authorization) model.

## Next steps

- [Sign up & sign in](/docs/authentication) — the flows behind the redirect.
- [Backend requests](/docs/backend) — validate the mobile session on your API.