A checksum is calculated on a database stored in a SIM card when changes are made to a database stored therein. This checksum can be stored in a mobile phone, e.g., with the change log. When synchronization between devices is to be performed, another checksum can be calculated on the database stored in the SIM card. If the stored checksum does not match the calculated checksum, then a change has occurred in the contents of the database that is not reflected in the change log. Accordingly, a full synchronization process can be performed wherein the database records in each device can be compared. If, on the other hand, the checksums match, then the change log accurately reflects any changes made to the database stored in the SIM card and the synchronization process can proceed more expediently using the change log.