You can use the net.rim.blackberry.api.messagelist package to create custom messages and folders for a BlackBerry® device application.

To use custom folders and messages in a BlackBerry device application, you must create an application with the following modules:

• a UI module for interacting with a BlackBerry device user
• a module for interacting with an application server and performing other actions in the background

Both modules are part of the same BlackBerry device application but have different application entry points.

You must determine the functionality that is part of each module. For example, a menu item that lets a BlackBerry device user delete a message or mark a message as read should be part of the daemon module. A menu item that lets a BlackBerry device user open or reply to a message should be part of the UI module.

• Creating a module for background processes
  
• Creating a module for the UI
  
• Create the module for background processes
  
• Start the module for background processes or the module for the UI
  
• Create an icon for a custom message
  
• Create a custom folder in the message list
  
• Send a notification when a custom folder changes
  
• Create an indicator for the number of messages in a custom folder
  
• Hide an indicator for a custom folder
  
• Remove an indicator for a custom folder