You can use a USB On-The-Go (OTG) adapter to connect your phone to a compatible USB memory stick or hard drive. For example, you can save your photos on a USB memory stick without needing to connect to a PC.
Connect the micro-USB end of the USB OTG adapter (available separately) to the micro-USB connector in your phone.
Connect a memory stick to the USB OTG adapter.
The Files app opens, and the memory stick is shown as a mass memory.
In Files, select and hold the file you want to copy, then select the option you want and the memory and folder you want to copy to.
If you connect a hard drive that needs more power than your phone can supply, an error message is shown. You need to connect an external power source to the hard drive.