Device came with a 128GB SD card, but I filled it up with ROMs and ISOs in like a week. Just grabbed a 256 GB one - can I just copy the current ROM folder to the new card, and put it in with no issues? Or would I need to do something more to keep shit safe?
Just copy all the contents of the SD card over to be safe. Retroarch might be storing files on the SD card and the BIOS folder might be separate from the ROMs.
There's a few Bios files I know are in the roms folder, but everything that isn't in the main android directory is in its own ROM folder, and I mean everything.