Here's my experience.
Best way I've found to get kill footage is a head-mounted camera. Head mount means 1 setup for wingshooting, bowhunting, muzzleloader, rifle, etc. Head mounted means you have automatic critter tracking software and hardware (You look with your eyes, Bert!) and less vibration from the shot.
Camera arms, tripods, and camcorders make for great footage, but are a drag to carry and keep nice in duck mud or deer thickets.
My phone takes good enough footage to entertain me, my friends, and (very surprisingly) thousands of Youtube viewers.
If you want to document your hunts for you and your buddies, I'd say a gopro for your noggin and a phone for b-roll, interview, hero shots, etc works fine. If you want semi-pro or pro results, you need much more gear and/or a crew, and your hunting will suffer. Those things are not in my want list.
FInally, if all you have is your cell phone, I find a lot of satisfaction watching a video of me going over my stand setup from the base of the tree, following the blood trail from first blood to the critter, and giving a short post-kill interview. 5 minutes of that can take me right back to that morning, doesn't cost much in terms of time and effort, and doesn't impede my hunting success.
I've been slow to video my hunts. I have dabbled with the youtube thing up to the point of monetizing and making dozens of dollars. That's been rewarding, but the most pleasant videos for me to watch are private videos I've uploaded of does feeding under my tree, ducks working to decoys after a limit, and post-kill interviews. For my personal amusement, a phone is really plenty.