Question about Timmkoo MP3 player with Bluetooth

The device has WLAN and Bluetooth as well as its own software for file transfer and file management. I have not seen a browser or access to download apps (I do this via PC).
I have and do as described in the answer above: memory expansion with SD card and file exchange with PC via USB cable.

You can also load files from the PC to the Timkoo via USB cable, for example we have an additional SD card in it with much more storage space.