@WeirdWriter Haha, if I can get people intrigued about Emacs of all things I know I've got the sales chops indeed! 😆
Yeah SyncThing is peer-to-peer, between machines on the same network like on the same internet router, no silliness like sending files to a server hundreds of miles away (where they can be compromised or fed to slop machines) just to share it between a computer and phone sitting next to each other! No need to fumble with data cables or ransack your drawers for a working thumb drive, just set up which folder syncs with which and bam, local wireless transfer smooth as your boyfriend's favorite vanilla bean-flavored lip balm.
I use SyncThing to sync and back up files between Arch Linux, Windows, and Android devices (Syncthing-Fork is better and less battery intensive on Android than the original Syncthing app) and haven't had trouble once I grokked its basic workings and twerkings. For example, deleting the .stfolder subdirectory in a shared folder will break synchronization, but don't panic if you do because you can simply create a blank .stfolder and it goes brrr again. Magic ✨