Trying to record smooth, aka not jerky, video with an iPhone or GoPro camera isn't exactly easy. We have all seen plenty of jerky videos. Not fun to watch.
Short of spending top dollar for large video stabilization systems, there aren't a ton of options available. That is about to change as a new video stabilizer, the StayblCam, is about to hit the market. Price and launch date are still a mystery. We will try and get our hands on one for a review as soon as possible.