The latest build of the MIUI 7 got a new feature called the Mi Drop. If you have been using apps like Share it, you would understand the need for such a feature. Just in case, you are not aware, the app creates a one to one wifi hotspot between devices and transferring large files between these two devices takes place almost instantly. Bluetooth transfers can be very slow and USB transfers are cumbersome. The Mi Drop is an inbuilt feature like many other features in the MIUI ROM. So if you have two mobiles with Mi-Drop enabled, you can transfer huge files instantly.
The downside of this feature is that, it works only between two devices that has the latest version of MIUI. To send files, just select the file(s) and choose MiDrop option from the sending methods. The receiving device must enable Mi Drop from the notification tray. The sender will see the reciving device on their mobile and selecting the device will instantly transfer the file.