"Rat Overpopulation" is a free lifestyle simulation game available on iPhone. The game allows users to manage a population of rats in a maze-like environment. Players can choose the number of units and rats to spawn, each unit consisting of a main room with a food bowl and water bottles, surrounded by smaller sleeping rooms. The objective is to keep the mischief of rats alive for as long as possible.

Players have the ability to individually place rats in the maze or release all at once. Throughout the game, users can observe and interact with the rats by dragging and dropping them within the maze. The game concludes when all rats perish, displaying a graph depicting the population decline over time.