The FileCommander are Sony in its smartphones with free, not always the most recent version. Now Amazon has this provided for the Kindle Fire HD at a good price. File Browser Apps there are many, often overloaded with all sorts. FileCommander focuses on browsing files, provides the file system, including libraries in a clearly arranged and includes a cloud services. Thus, now comes with the Kindle Fire HD and the Google Drive and others. The interface is attractive and very intuitive. In my Android smartphones I had the app on Google Play reinstall so that the cloud services functioned, so look for the installed via the Amazon App Store app in Google Play (displayed as installed), then uninstall and reinstall Google Play.