Methods, systems, and apparatus, including computer program products, for reusing components from an application are provided. In some implementations, a method includes associating a parent and child component in a source application. The components are used in the presentation of document data during navigation among documents. A navigation interface in an application window of the source application is presented, including presenting document data according to the parent and child components. Input adding the parent component from the source application window to an application window of a target application is received. It is determined that the output of the child component is connected with the input of the parent component, and then computer-readable instructions associated with the parent component and the child component are inserted into the target application. A navigation interface is presented in the target application window, including presenting document data according to the parent and child components.