Social sign-in for native and mobile apps

Overview

This page covers how to implement social sign-in for native applications via OIDC and OAuth 2.0. The user interaction looks like this:

• The user is presented with a login or registration screen that includes a social sign-in button.
• The user clicks the social sign-in button. A browser window opens (using ASWebAuthenticationSession on iOS or Custom Tabs on Android).
• The user authenticates with the identity provider and grants the application access to profile information.
• The user is redirected back to the application and is logged in.

note

Apple and Google support a more tightly integrated login experience for native apps. See the documentation on Apple social sign-in and Google social sign-in for more information.

The native app authentication flow

From a high level, the native app initializes a login or registration flow and receives the first part of the session token exchange code from the Ory Network. After the user performed the social sign-in, the user is redirected back to the native application via an iOS Universal Link or Android App Link. The native application then exchanges the session token exchange code for a session token.

info

As part of this flow, Ory will redirect the browser to a callback. In this demo, we use the redirect URL http://localhost:19006/Callback. Please ensure that this redirect URL is allowed. Go to Branding → Browser redirects in the Ory Console to allow it.

The flow looks like this:

Implementation

The following sections describe how to implement the native app authentication flow. The code examples are written in TypeScript for React Native. The steps refer to the steps in the flow diagram above.

Steps 1-5: Create an API flow with return_session_token_exchange_code=true

The user opens the login screen (1) and the native application initializes a login or registration flow through the Ory Network APIs (2) with the following parameters:

• The flow is of type api.
• The return_to parameter is set to the URL of the native application. This URL is used to redirect the user back to the app after the social sign-in.
• The return_session_token_exchange_code parameter is set to true to receive the session token exchange code in the response (3).

src/components/Routes/Login.tsx

see full code on GitHub

Upon rendering the form, the user selects the specific social sign-in provider (4). The native application submits the form to the Ory Network (5).

Steps 6-12: Open the identity provider authentication URL in a browser

Ory Network returns a 422 status code if the user needs to perform a social sign-in from a flow of type api (6). The response contains the URL of the identity provider in the redirect_browser_to field.

src/helpers/form.tsx

see full code on GitHub

WebBrowser.openAuthSessionAsync opens a browser tab for authentication for the specified url (7+8). Implementations in other languages and frameworks may vary.

src/helpers/form.tsx

see full code on GitHub

The user authenticates with the identity provider and grants the application access to profile information (9). The identity provider then issues a redirect to the Ory Network callback URL (10), which the browser follows (11).

Steps 12-14: Exchange the session token exchange code for a session token

Finally, Ory Network issues a session for the user and redirects the browser to the application's return_to URL (12). The native application receives the second part of the session token exchange code in the code URL query parameter. In the example below, the call to WebBrowser.maybeCompleteAuthSession is used to close the browser tab and return the control flow to the code that awaited the call to WebBrowser.openAuthSessionAsync.

src/components/Routes/Callback.tsx

see full code on GitHub

The native application then exchanges the session token exchange code for a session token (13) using the first part of the code returned from the flow initialization, and the second part of the code returned from the return_to query parameter.

src/helpers/form.tsx

see full code on GitHub

Finally, the native application stores the session token in the secure storage (14) and redirects the user to the home screen.

src/helpers/form.tsx

see full code on GitHub