Shows correct set up and usage of https://github.com/aws/amazon-cognito-identity-js in a Demo Application. The Application allows a user to sign-up with different User-Atrributes. It can be used with MFA settings enabled.
First step:
Clone this project and download the following Libraries to a folder named /dist:
- /dist/aws-cognito-sdk.min.js
- /dist/amazon-cognito-identity.min.js
- JavaScript BN library
- Stanford JavaScript Crypto Library
For more information about the dependencies click here
Second step: Go to the AWS Cognito User Pools and create a new User Pool: For the settings used in this application enable MFA and choose next to `email` as required attribute `phone number`.
When creating the Client app it's IMPORTANT to uncheck the generate client secret box. Because the JavaScript SDK doesn't support apps that have a client secret. 
Third step: Go to AWS Cognito Federated Identites and create a new Identity Pool for your User Pool.
For your Identity Pool you can create a Authenticated role as well as a Unauthenticated role, where you can define what your users are allowed to do. For example reading from/uploading to S3.
Forth step: After you created all necessary AWS rescources, you need to reference them in your application. For that open the file `config.js` and edit the variables. The Ids like `identityPoolId` or `UserPoolId` you are able to see in the AWS Console.
Great, be your first user Open `index.html` in your browser and sign up for your client app.
Article about Amazon Cognito in the Browser.
Here you can find the docs for Official amazon-cognito-identity-js
The kiwi background pattern can be found here