I have been going though the Android documentation searching for a way to identify a USB device (mass storage device or other) by its UUID, but I don't find one.
I looked at:
UsbDevice Docs
UsbManager Docs
USB Dev guide
Non of these provide a sufficient method of determing the UUID.
Looking at some of the methods in UsbDevice, I would possibly go for getDeviceID(), however it
Returns a unique integer ID for the device. This is a convenience for clients that want to use an integer to represent the device, rather than the device name. IDs are not persistent across USB disconnects.
As a side note, I am using this library (libaums) to communicate with a FAT32 USB Mass Storage Device
How can I get the UUID of a USB mass storage device on an Android phone?
https://developer.android.com/reference/android/hardware/usb/UsbDevice.html#getSerialNumber() should uniquely identify the device.