alt-sendme—Out-of-the-Box File Transfer Tool

sharedrop—WebRTC-Based Cross-Device File Sharing

sftpgo—SFTP Server with Integrated Cloud Storage

FlyingCarpet—Network-Free File Transfer Tool

kdeconnect-kde—Device Interconnectivity Tool on Linux

localsend—Open-Source Alternative to AirDrop

magic-wormhole—Simple and Secure Peer-to-Peer File Transfer Tool