The folder view will display the contents of any folder added to the scanner paths in the scanner settings. If multiple folders are added to the scanner, the top level of the folder view will list them all. If a single folder is added to the scanner, the top level will show the contents of that folder. At the top of the folder view under the toolbar there is a quick navigation bar that lets you to jump up multiple folders at a time.
Note: The folder view will only display files supported by GMMP