[quote="Leo, post:6, topic:25347, full:true"]
It's not usually complicated at all. You just download an SFTP or FTP server app from the Android store[/quote]
Yes, quite simple. I recently tested a few apps and settled with Primitive FTPd.
It's free, rather pretty, doesn't show ads and even has an on/off widget.
BTW: I noticed FTP works best if you navigate top-down and avoid wild jumps within the tree structure.
If you don't want use FTP, don't even think about Bluetooth!