Access OTG devices through OTG USB File Explorer application.
OTG USB File Explorer for android allows you to 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.
You can easily copy files from any USB mass storage device to your Android Phone, Tablet (rename, add folders, delete files etc..)
Root access is NOT required.

OTG stands for On The Go.