Step 2: Set up Apple Service ID

• Generate a Service ID:
  • After your App ID is created, navigate to the Certificates, Identifiers & Profiles page again.
  • Click on Identifiers, then on the "+" button.
  • Select Service IDs and click Continue.
  • Provide a description (e.g., "Your App's Service ID") and enter a unique identifier (this will be the Service ID used in OAuth, e.g., com.yourcompany.serviceid).
  • Click Continue, and then click Register.
• Configure Redirect URIs:
  • After creating the Service ID, you’ll be redirected to the details page for the Service ID.
  • Scroll down to the "Sign in with Apple" section and click on Configure.
  • In the "Domains and Redirect URLs" section, add your app’s Redirect URI (for example, https://yourapp.com/auth/callback).
    • Ensure this URI matches what is configured in your app’s authentication flow.
  • Click Next, review the configuration, and then click Save.
• Configure App's Sign-in Permissions (Optional):
  • In the Web Authentication Configuration, you can specify which users can sign in with Apple using your Service ID.
  • Typically, leave the settings to the default unless specific conditions are needed.
• Generate Key for Sign in with Apple (Optional):
  • If you need to verify tokens on your server, go to the Keys section under Certificates, Identifiers & Profiles.
  • Click on the "+" button to create a new key.
  • Enable Sign in with Apple, then create a key and download it. You'll need this key on the server to verify identity tokens.