yes, you can transfer files over WiFi without any program / application . it works just by using web browser . it works based on WebRTC protocol (peer to peer – p2p protocol) It is a cross platform you can use in any device Android / ios / windows / Linux . it’s completely open-source and free and Does not require sign up.
offline file transfer p2p over wifi on phone/laptop support any operating system(os)
Step 1 : Make sure your device’s connected on a same WiFi (or) share one’s internet using WiFi tethering
Step 2 : Open -> snapdrop.net website on both of your devices – the sender and receiver will discover each other’s devices instantly 
Step 3 :
Sender – just tap on the device and select a file to send,
Receiver – you will get a notification either to download the file or ignore it. select the download button to get the file on your device .
that’s it. 
You can even use this site completely offline . all you need to do is just install this as a WebApp by clicking the install button in the address bar 
Other Websites to try out : https://www.sharedrop.io/ , https://file.pizza/ , https://takeafile.com/
❤ XOXO ❤