To the right, on the main screen, are a collection of sniggering green pigs, sheltering under a structure made out of wood, concrete, steel or ice. To the left are Iisalo’s legless, cross-eyed birds, whom you must launch through the air at the pigs, using a catapult. Points are scored for destroying the forts, which become increasingly elaborate, and squashing the pigs. The only thing a player needs to operate the catapult is their finger. When I tried the game for the first time, my friend’s five-year-old daughter showed me how to play.