Peer-to-peer file transfers in your browser Cooked up by Alex Kern & Neeraj Baid while eating Sliver @ UC Berkeley.
Using WebRTC, FilePizza eliminates the initial upload step required by other web-based file sharing services. When senders initialize a transfer, they receive a "tempalink" they can distribute to recipients. Upon visiting this link, recipients' browsers connect directly to the sender’s browser and may begin downloading the selected file. Because data is never stored in an intermediary server, the transfer is fast, private, and secure. (Your PC must be online while the recipient download the file(s), if you shutdown the PC or goes offline, the download also stops)
You can selfhost it or use the official instance
https://github.com/kern/filepizza
You can't really do this on the web as devices can't directly connect to one another. You need some signalling server to bootstrap the transfer. However almost all of these WebRTC services will actually do the transfer locally if both devices are connected to the same network and can talk to one another directly.
So you would need a native application.
Yes but I was talking about the same network :)
LocalSend does exactly what I wanted