It is going to be a while before I get a iPhone 5. I have a 4S, but I don't think there is a slow-mo option. Or at least I haven't found it.
On a sort of related note, I was watching people fire at the last Rock Your Glock match. The sun was coming up from behind us, and you could see some of the slower bullets moving downrange. That is one of the coolest damn things I have seen for a quite a while. I am wondering if the video on one of the better smart phones could pick the bullets up. Probably not, as advanced as they are, the human eye is pretty darn amazing.
ETA: Just my two cents...I zoomed in on the video, and from what I can see the web of the hand is not completely up as high as it can go on the back of the pistol grip. If not, moving it up will help with some of that snap she is getting in the wrist.
Fly