It allows you to use certain models of Samsung phone as your "key" to open & start the car instead of using your actual key
It works by using a secure contactless chip in your phone acting as the key - just hold your phone against the door handle to open, and pop it on the phone charging tray to start the car. Convenience.
Drawback is that it presently only works with certain Samsung phone models, not other Android brand phone and not Apple devices as well