Video drone that flies itself

Two Silicon Valley start-ups are hoping to change the way sports enthusiasts capture their best moments on camera.

The Hexo+ and the Airdog drones autonomously follow the user from the skies, tracking their position from either a smartphone (Hexo+) or a wrist-worn device (Airdog). Each has a camera-equipped stabilising rig, can fly for about 10-15 minutes on a single battery and can travel up to speeds of around 40mph.

Both drones have smashed their investment targets in a matter of days on the crowdfunding website, Kickstarter.

But how safe are drones which have little or no user-intervention?

The BBC's North America tech correspondent Richard Taylor took the Airdog for a whirl - and met its Latvian founder and chief executive Edgars Rozentals.

Follow Richard Taylor on Twitter @RichTaylorBBC