Nintendogs uses the DS’s touchscreen and built-in microphone. The touch screen allows the player to pet a dog, as well as to use various items that can be found or purchased. These range from balls and frisbees, to toys, to grooming supplies to keep the dogs happy. The microphone is used to call to the player’s dog by speaking the name given to the dog in the beginning of the game as well as to teach the dog tricks such as “sit” or “roll over”. Players can bring their dogs on walks and to the park if they so choose. They may interact with other players in multi-player by using the DS’s wireless linkup. It also uses the DS’s internal clock and calendar to allow the dog to grow hungrier or dirtier based on the elapsed time.