In an information system including an information processing apparatus and an in-vehicle apparatus, a synchronization process is performed in a highly efficient manner, which allows an improvement in usability in playing back playable data on the in-vehicle apparatus. The information processing apparatus acquires a list of playable data already existing in the in-vehicle apparatus and produces synchronization data by extracting, as the synchronization data, playable data from the playable data existing in the information processing apparatus in accordance with the acquired list such that the extracted playable data does not include any part of the playable data already existing in the in-vehicle apparatus.