As an auth backend to an app, perhaps, but the web login forms for Cognito had terrible UX (when we were using it). So terrible that we had daily customer-reported support tickets that we had no ability to fix (short of writing our own full UI).
Also, sharding user records into Cognito pools was a bit frustrating. Hopefully AWS has invested in fixing these issues.
Also, sharding user records into Cognito pools was a bit frustrating. Hopefully AWS has invested in fixing these issues.