A composite application is made up of portlet applications and services that present data from multiple resources on one or more webpages for the end user. Composite applications are also used to create modernized front ends for legacy systems. Suppose you have a mainframe program that stores customer orders and the names of sales representatives. You could create a customer management composite application that pulls that data from the mainframe program and displays it on a webpage. When the end user clicks an order, the composite application gets the order details from the mainframe program and displays it on another webpage. When the end user clicks a sales representative, the composite application gets customer data from the mainframe program and displays the locations and contact information for the sale representative's customers on a Google map.

The primary products that developers use to develop composite applications are Software AG Designer and Application Platform. Developers might also use CentraSite. The products that execute composite applications are My webMethods Server and Integration Server.