After messing around with the GoPro Hero4 Black and some of the photography equipment I have I found a few things that could be pretty helpful to all the photographers out there that have a GoPro.
First, the cases that come with the battery adaptor for Nikon prosumer bodies can hold two GoPros almost perfectly. This is pretty nice if you want to carry your GoPro with you in a camera bag or just for storage.
The second is for photographers that have a lot of grip for lighting laying around super clamps with the studs and magic arms make great mounting points for the GoPro. You just need to get the GoPro 1/4" stand adaptor.
Finally, I found while shooting 4K video the battery doesn't last very long and it doesn't last much longer with a the GoPro battery bacpac. I have a Alienbees Vagabond Mini Lithium that has two 120V outlets (which is great for studio lights) but it also has a USB charger. You can plug your GoPro into the USB charger and get super extended battery life out of a very portable pack.
Hope these tips gave you some ideas to use.