Essentially, you capture a photograph of a friend through the app’s viewfinder, and then you press on their face. If face detection recognises that a headshot has been made then an animation is generated showing your friend getting furiously pasted by your selected weapon - as well as a ‘crow’ animation carrying your actual face gloating in one of our skins.

This game is perfect for multi-storied carparks or department stores - any building blessed with multiple staircases and open access to do battle over multiple floors.

It is easy to capture a headshot of someone unawares, extremely difficult if they know you are coming. This dichotomy is why snipers operate behind enemy lines, why celebrities are harder to capture than Joe Public, and why photo combat is so much fun.

if you are keen to invent some of your own games here are a few things you might want to consider.

My mum may prefer herself in a muscle vest. Whether or not she chooses to try the new look out on her friends is up to her.

Naturally, I bludgeoned him over the head with a press gang baton and locked him in a dungeon.