I was flying a mini-drone and noted that it had an extremely accurate return-to-home feature. All you had to do was press the Home button on the remote control, and with the help of GPS and sensors, it would return to home from anywhere, automatically landing within inches of its departure point.
I also learned that you could pre-program a different home point or even change the home point while the drone was in flight, and it would instead land at that point, useful if you had to change your physical location while flying.