I hope for your own sake that you're not one of those irresponsible guys who can be seen interacting with GoPro's mobile app on their smartphone while skating, parachuting or cycling. If you are, however, you might want to download GoPro's latest iPhone app which now includes a native Apple Watch app that lets you start and stop recording with a simple tap on your wrist.
Less time spent starring at the smartphone screen gives you more time to avoid those obstacles. What do you mean, you don't skate?