Another very short write-up about some of the services that might appear in the exam certification.

Amplify

It provides tools and features for building full-stack applications on AWS (even with no or very little backend experience)
Amplify Studio is a visual interface to define data model, user authentication and file storage.
Broad sets of Amplify libraries for iOS, Android, Flutter, React Native and Web
Amplify Hosting is a fully managed CI/CD and hosting service

I had used Amplify in the past just to set up authentication in a React application and to get S3 signed urls, but not much more. personally, as much as I find Amplify studio useful for "getting stuff done quickly" I don't find that much interesting for production workloads in big teams

AppSync

is a fully managed service that makes easy to develop GraphQL APIs, so that application can access, manipulate and receive real-time updates from multiple data sources ( resolvers will grab and aggregate sources like Elasticsearch, DynamoDb, Lambda)
it automatically scales, provides server-side data caching ( without need of managing cache clusters )

AWS Serverless Hero Yan Cui has some very interesting articles ( and courses ) about AppSync, defenetely worth a look!

AWS Device Farm

is an app testing service that lets you test and interact with Android, iOs and web apps on many devices at once.

No need to purchase and maintain a collection of devices for you dev and qa testing anymore.

you can perform automated testing and manual testing with through remote access to interact with a real device through the browser.

Devices are non-rooted and any appropriate app can be installed.
you can simulate real world environments, selecting languages, locations and so on.

AWS Pinpoint

Amazon Pinpoint allow to deliver customer communications across channels, segments, and campaigns at scale.

• collect app usage data
• built in analytics
• import data from s3 or redshift ( or csv files ) to build segments
• build campaign messages and schedule campaigns
• analyse campaigns
• funnel analytics