An app which functions when you place the iPhone vertically in such a fashion that both hands are on each side of the phone, facing both cameras.

You don’t need a stand, you could also use a salt and pepper shaker, a wedge of plasticine, your girlfriend/boyfriend’s knees...

Sheesh, try to be less pedantically rigid, honestly .. it’s a cool app idea. All it takes is for the user to mount their phone vertically while they’re using it.