Prefer to build from source? Get the code on GitHub.
PhoneDrop is a small desktop utility that transfers files from your computer to a mobile device over a local network. You can drag-and-drop files into the window or use the system's "Open With" menu (on Linux) or straight up "Send to phone" on Windows to generate a QR code. Scanning the code with a phone opens a temporary local web interface to download the files directly without using cloud services or accounts.