Set up App-to-App Account Linking for Your Skill
If you have an app or website and can obtain an authorization grant for your user without requiring them to log in again, we encourage you to implement one of the app-to-app account linking flows in addition to the Alexa app-only flow.
There are two app-to-app account linking flows you can implement. In one flow, the user starts the process from your app or website. In the other flow, the user starts the process from within the Alexa app.
In this section
App-to-App Account Linking (Starting From Your App) – In this flow, the user acknowledges the account linking request within the Alexa app (or Login with Amazon), and is then redirected back to your app or website, which completes account linking and enables the skill by using APIs provided by Alexa.Note: For app-to-app account linking (starting from your app) best practices, see Best Practices.
App-to-App Account Linking (Starting From the Alexa App) – In this flow, the user starts the process from within the Alexa app by enabling the skill or by clicking on the Link your account option on your skill's detail page. If the user has your app installed on their device, the device launches your app and asks the user to acknowledge the account linking request.
After the user acknowledges the request, the device returns the user to the Alexa app. If the user doesn't have your app installed on their device, the flow is the same as the Alexa-app only account linking flow. That is, the user's browser opens your authorization page, which asks the user to acknowledge the account linking request. After the user acknowledges the request, the authorization website returns the user to the Alexa app.Note: For app-to-app account linking (starting from the Alexa app) best practices, see Best Practices.
Alexa Skill Activation API – The Alexa Skill Activation API enables you to enable and disable an Alexa skill for a user, and link the user's Amazon account with an account in another service. App-to-app account linking uses this functionality.