Settings

From the hamburger menu, go to App Engine | Settings. Here, you will find two important settings: Custom domain and SSL certificates. Let's go over these now.

Custom domain

As you already know, when you deploy an application, you are assigned a URL in the form of <project_id>.appspot.com.

You can, however, add a custom domain or register a new domain. You do this from the App Engine | Setting | Custom domains menu:

If you choose to register a new domain, you will be able to purchase it from the Google Domains service.

SSL certificates

Since the traffic...