Amplify Cognito: Authenticator Default Language

To switch the default language of the Amplify Authenticator component from English to German, you have a couple of options:

1. For the Amplify SwiftUI-based Authenticator component: You can add a string file to your project to provide strings for other languages. For German, you would create a string file with the appropriate translations. For example:

   "authenticator.signIn.title" = "Anmelden";
   "authenticator.signIn.button.forgotPassword" = "Passwort zurücksetzen";
   "authenticator.signIn.button.signIn" = "Senden";
   "authenticator.signIn.button.createAccount" = "Konto erstellen";
   

   This method allows you to customize the text for various elements of the Authenticator UI.

2. For the Cognito Hosted UI: If you're using the Cognito Hosted UI, you can add a 'lang' query parameter to the URL that you distribute to users. For German, you would use:

   https://your-domain.com/oauth2/authorize?lang=de&response_type=code&client_id=your-app-client-id&redirect_uri=your-relying-party-url
   

   After a user makes a request with this parameter, Amazon Cognito sets a cookie in their browser with their language preference. This means the language selection will persist for future visits unless they clear their cookies or make a new request with a different language parameter.

It's important to note that while these methods allow you to change the language, they don't automatically set German as the default for all users. The first method requires you to implement the language selection logic in your app, while the second method requires you to include the language parameter in the URL you provide to users.

If you need to set German as the default language for all users without requiring them to select it, you might need to implement a custom solution, such as detecting the user's browser language and applying the appropriate localization, or setting a default language in your app's configuration.
Sources
New – Amplify SwiftUI-based Authenticator Component | Front-End Web & Mobile
User pool managed login - Amazon Cognito