Walk around and shoot zombies. Shoot at them with guns, stab them with knives, blow them to smithereens with explosives, and block them out with barricades. Earn cash from attacking zombies to buy health, repairkits, perks (will be added later), map specific features (in later updates) and weapons.

Thanks to http://nintendomax.com/viewtopic.php?t=13405&f=19 for the news.