http://www.valuewalk.com/2015/08/slick-gopro-stabilizer/

"Romain Dillet of TechCrunch tried a Slick prototype first-hand. He said the stabilizer was amazing especially when you look around. Instead of recording the sudden movements, the camera smoothly moves from one angle to another. This accessory may not be for everyone. But a large number of GoPro video professionals may find it useful. It works with almost all the GoPro cameras, including the recently announced Hero4 Session.
Slick launched it Tuesday with an Indiegogo campaign. The startup has priced it at $199, and plans to start shipping the accessory in March 2016."

Hm. If this doesn't weight too much, it might be good on a quadcopter.