Pixatel's File Manager is a lightweight Android file manager. At 448KB, it's smaller than many images and dwarfed by the megabyte competition. File Manager isn't as stylish or feature-laden as the heavy hitters, but it's easy to use, fast, and uses fewer resources. It's free but displays banner ads.
As we noted, Pixatel's File Manager lacks the pizzazz of heftier apps, though stylish themes won't make your stuff any easier to access when you need it. File Manager's scrolling list view of folders and files could hardly be easier, and an equally basic but functional toolbar handles everything else, including adding folders and deleting, copying, and moving folders and files. A "Sort by" button, a Search tool, and Tool Box with an Application Backup utility that can back up all your apps round out File Manager's toolbar. The Settings only allow you to show hidden files, image previews, and storage information, or not. Pressing the "i" button shows the file and folder totals of any folder you select, but there's no Help file or similar resource. File Manager is intuitive and easy to use, though, so most won't need any guidance.
It might not be much to look at, but File Manager has a light touch and small footprint. It just does more with less.