Add USB drives and browse them with FileBrowser Professional, you can also map other apps shared folders such as Firefox's Download folder for instant access in FileBrowser Professional.
You can add multiple USB drives and FileBrowser Professional will remember them.
An easy way to free up storage on your iPad / iPhone is to keep large files on a SanDisk iXpand drive. Simply plug it in and it will appear as another location in FileBrowser Professional.
FileBrowser Professional can map the folders of other apps such as FireFox's Download folder or PDF Viewer's folder for easy access and manipulation.
Map an iCloud folder for direct access in FileBrowser Professional.