Not much really. So far it seems too good to be true. The perfect mini camera. It's the finest yet in the GoPro evolution and now with 4K. So what can the GoPro Hero 4 not do? For videography it can do nearly everything, but it can not shoot the video for you. For the inland surfer it can capture all of the best moments, but it cannot experience them for you. Beyond the lens of a camera you are the most important piece. You + GoPro. Pick one up and get creative.
Here is what you can expect from the new Hero 4: