Communication system, information processing apparatus, computer-readable storage medium, and communication method

Prior to performing download play, it is determined whether or not a slave apparatus program has been already stored in an internal memory of a slave apparatus. When not stored yet, the slave apparatus program is transmitted from a master apparatus to the slave apparatus, and stored in the internal memory of the slave apparatus. When already stored, the slave apparatus program is not transmitted from the master apparatus to the slave apparatus. Then, multiplay is performed by performing mutual communication between the master apparatus operating in accordance with a master apparatus game program and the slave apparatus operating in accordance with a slave apparatus game program. Thus, time and effort for receiving the same application program more than once are omitted, and it is possible to efficiently start a communication process.