A free app for Android, by Live Video Tool.
OTG USB Driver For Android is an app that lets you manage files from any USB mass storage device with a FAT32 or NTFS file system using the USB OTG port of your device, tablet, or phone.
The application allows you to view, copy, move, rename, and unzip files. You can also delete files and folders, create new ones, and compress files.
The application supports the FAT32 disk format of flash drives. It is possible to connect an external disk or the USB stick further. For an output of more detailed information, it is possible to use the mounted button.
It is possible to connect more than one device to the same phone or tablet.