Abstract: A synchronization program (54) receives setting information of a first application (31) via a connection program (32) of a cloud server (3) in response to a login operation on a client apparatus (5), generates a database (532) of a second application (53) and synchronizes a display screen (531) of the second application (53) with a display screen (311) of the first application (31). The synchronization program (54) further receives data in a database (312) of the first application (31) via the connection program (32) of the cloud server (3) and synchronizes data in the database (532) of the second application (53) with the data in the database (312) of the first application (31).