Amazon Cognito

//Android
// 1) -- Create an instance of Auth --
Auth.Builder builder = new Auth.Builder()
  .setAppClientId(getString(R.string.cognito_client_id));    
  .setAppCognitoWebDomain(getString(R.string.cognito_web_domain));
  .setApplicationContext(getApplicationContext());
  .setAuthHandler(new callback());
  .setSignInRedirect(getString(R.string.app_redirect_signin));
  .setSignOutRedirect(getString(R.string.app_redirect_signout));
  .setScopes(userScopes);
  auth = builder.build();
 
// 2) – Set up url redirect in your app manifest --
<intent-filter>
  <data android:host="YOUR_REDIRECT_URI_AUTHORITY"android:scheme="YOUR_REDIRECT_SCHEME"/>
</intent-filter>
 
// 3) -- Get tokens for your user --
auth.getSession();

// iOS Swift
// AppDelegate.swift
func application(_ app: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any] = [:]) -> Bool {
  return AWSCognitoAuth.default().application(app, open: url, options: options)
}
// ViewController.swift
let cognitoAuth = AWSCognitoAuth.default()
cognitoAuth.getSession(self)  { (session:AWSCognitoAuthUserSession?, error:Error?) in
  if(error != nil) {
    print((error! as NSError).userInfo["error"] as? String)
   }else {
   //Do something with session
  }
}

// Add 'aws-amplify' and 'aws-amplify-react-native' libraries into your application

// Configure Auth category with your Amazon Cognito credentials
Amplify.configure({
    Auth: {
        identityPoolId: 'XX-XXXX-X:XXXXXXXX-XXXX', // Amazon Cognito Identity Pool ID
        region: 'XX-XXXX-X', // Amazon Cognito Region
    }
});

// The withAuthenticator component adds Sign Up and Sign In capabilities to your app 
export default withAuthenticator(class App extends React.Component {
     // ... your main component
});

// Add 'aws-amplify' library into your application

// Configure Auth category with your Amazon Cognito credentials
Amplify.configure({
    Auth: {
        identityPoolId: 'XX-XXXX-X:XXXXXXXX-XXXX', // Amazon Cognito Identity Pool ID
        region: 'XX-XXXX-X', // Amazon Cognito Region
    }
});

// Call Auth.signIn with user credentials
Auth.signIn(username, password)
    .then(user => console.log(user))
    .catch(err => console.log(err));