Which service allows developers to build and monitor mobile applications?

The correct choice is AWS Mobile Hub, which is specifically designed to provide a comprehensive environment for mobile application development. AWS Mobile Hub offers developers tools to build and monitor mobile applications with ease. It provides a variety of back-end services that simplify the integration of features such as user authentication, data storage, push notifications, and analytics. The service also includes a dashboard to monitor the health and performance of mobile applications, making it an essential tool for developers aiming to create robust mobile experiences.

AWS Mobile Hub's main advantage is that it abstracts the complexities associated with multiple AWS services, allowing developers to focus on building their applications rather than managing underlying infrastructures. This integration enhances productivity and accelerates the development process. Also, Mobile Hub aids in managing resources and can automatically generate code snippets, streamlining the development workflow.

In contrast, AWS Device Farm is primarily aimed at app testing across real devices to identify bugs and issues before an app is released, while Amazon Pinpoint is focused on user engagement and analytics, providing features for targeted communication such as email, SMS, and push notifications. AWS Shield is a security service for protecting applications from DDoS attacks and is not related to application development or monitoring. This contextual understanding clarifies why AWS Mobile Hub stands out as the correct