Geronimo applications can refer to common JARs installed in the Geronimo repository or included in the Geronimo shared library directory. This makes it easy to reduce the footprint of application modules and share JARs across multiple applications. Geronimo applications can also customize which classes are exposed from parent class loaders, and configure the parent/child class loading priority.

The Geronimo J2EE distribution includes a web-based administration console, including configuration options (such as network ports), wizards (to create database pools, security realms, etc.), monitoring screens (for thread pools and memory usage), deployment tools, and more. Certain plugins extend the administration console as well.

Geronimo supports clustering of web applications for fail-over and scalability.

The Apache Directory LDAP server can be run within Geronimo.

The Quartz scheduler can be run inside Geronimo, and scheduled jobs can be deployed as standalone modules or as part of J2EE applications.

The Liferay enterprise portal can by run inside Geronimo.

For cases where a full J2EE server is not needed, the Little G distribution offers a web-focused distribution with the same foundation as the full Geronimo server, but a much smaller footprint. Little G includes a web container, transaction manager, database connection pools, the same security, logging, and deployment tools, the Geronimo Plugin system, and more. However it omits support for EJBs, JMS, Web Services, and the administration console. If you need more than Little G, you can either add back features like JMS using Geronimo Plugins, or start with the J2EE distribution and simple disable or remove the features you don't need.

Geronimo developers can integrate Geronimo into Eclipse using the Geronimo Eclipse plugin. Leveraging the Eclipse Web Tools Project, this plugin lets you run Geronimo in Eclipse (including starting, stopping, deploying to, and debugging Geronimo), generate code for Geronimo, debug into JSPs running in Geronimo, and more.

Geronimo provides plugins for Maven 1, which can be used to start and stop Geronimo, deploy applications to Geronimo, build Geronimo Plugins, and more. With these plugins, a Maven build can compile and build an application, start Geronimo, deploy the application, run a number of tests, and finally shut down the Geronimo server. Maven 2 plugins are under development for the next release of Geronimo.