Page zero of your application functions as a master page. The Application Express engine renders all components you add to page zero on every page within your application. You can further control whether the Application Express engine renders a component or runs a computation, validation, or process by defining conditions.
To create a page zero:
On the Workspace home page, click Application Builder.
Select an application.
The Application home page appears.
Click the Create Page button.
For Select a page type, select Page Zero.
Note that the Page Zero option only appears if the application does not have a page zero.
Click Finish.