I have used PhotoSync App(not free, this is not a promotion) for transfers between iOS, Android, Windows and Mac. It also supports transfers via (S)FTP, SMB or

I have used PhotoSync App(not free, this is not a promotion) for transfers between iOS, Android, Windows and Mac. It also supports transfers via (S)FTP, SMB or WebDAV, hence Linux (I have not tried this). https://www.photosync-app.com/home https://www.photosync-app.com/home There may be other apps that set up a server (i.e. http, ftp ...) on the phone. Ask Google.