Serverless platforms like Azure Functions and Azure Container Apps simplify application scaling by eliminating the need to manage infrastructure, but they require careful planning to address challenges like cold starts, unpredictable scaling, and secure data handling. The Azure Well-Architected Framework provides a foundation for building robust serverless applications by focusing on reliability, performance, security, cost optimization, and operational excellence. Datadog supports these pillars by offering insights into serverless environments, helping ensure applications are secure and efficient. Reliability involves managing high availability and function failures, while performance can be improved by minimizing cold starts and optimizing function processes. Security is enhanced through role-based access control, authentication, and encryption, while cost optimization requires selecting the right pricing plans and reducing idle execution. Operational excellence is achieved by integrating observability into applications, and Datadog's tools provide comprehensive monitoring, tracing, and security features to help maintain and improve serverless application performance on Azure.