Not knowing much about drones, I had no idea consumer drones can fly that high! Apparently, the maximum spec height is 6 km which is impressive on its own. And this thing went 3 km higher than the spec. I had always assumed they can't rise above two or three thousand feet max.
The most impressive drone going now to me is the one NASA put on Mars since it's working at the equivalent atmospheric pressure of around 100,000 feet, though the lower gravity helps it out. Obviously it's not a consumer drone, but it used as much off-the-shelf gear as possible - I think I remember reading it just uses a few Sony 18650 lithium ion cells like you might find in your cordless drill.
