How SD Card File Transfer to Your R36S Game Console

Folder Structure

BOOT partition

This is where dtb files and bootlogos are stored.

EASYROMS partition

This is where all the roms (games), launchimages, themes, backups and background music are stored. For a full list of all rom folders and supported filetypes, please refer to the ArkOS wiki

If you can't access the EASYROMS partition, you probably need to assign a drive letter in Disk Management. Here's a short video how to do this. 

Accessing the SD card on Android

It's also possible to copy over files with an Android device. But be aware that android automatically creates a few empty folders if a SD card is connected. You can use any file manager that you like. Below are a few examples ("TS-RDF5 USB drive" is the microSD card adapter in this case).