Octopus Deploy 4.1 introduces new capabilities for managing application deployments and certificates, particularly for deploying web applications in Tomcat using artifacts from Maven repositories. The blog post outlines a demonstration of these features by deploying a demo application in Tomcat 9 on Windows 2016, integrating Maven Central as an external feed in Octopus to facilitate artifact consumption. It also covers generating and deploying a self-signed ECDSA certificate to secure the application, setting up deployment projects in Octopus, and configuring Tomcat for HTTPS using the NIO2 SSL implementation. The process includes creating a deployment project in Octopus, utilizing built-in steps to automate application and certificate deployment, and verifying the deployment result by accessing the secured demo application. The blog emphasizes Octopus's ability to streamline the deployment lifecycle with these built-in steps, highlighting its utility for automating Java application deployments.