[root] StickMount is an application for file management on connected storage (USB sticks, for example) by OTG cable on rooted Android devices. It was originally and made for Nexus devices (although it is known to work on many other Android devices with root access) to solve the problem of automatic mounting because some of these devices were not able to mount USB sticks. Android users with rooted devices can try StickMount 3.26 out on their devices by downloading the APK file with the link below.
How to use StickMount 3.26
After you install StickMount 3.26 on your Nexus (or other device, experimentally), launch it, connect your USB stick, and start exploring your USB stick. StickMount has a special algorithm for media scanning and it will automatically add images and music to your gallery. This operation works in the background, but if there is a folder that you don’t want to be scanned, you just have to put a file named with “.nomedia” in that folder. When you put it in the root folder, the whole USB stick will not be scanned. StickMount supports many file types on your USB stick, whether it was FAT format for reading and writing, or NTFS format for read only, it depends on your device and your version of Android OS.