Nowadays, the major manufacturer of the mobile devices has offered its own solution for the data synchronization. But each manufacturer uses its proprietary data synchronization method so that the compatibility of data can not be guaranteed. To solve such problems, a gateway is needed to convert different forms of data into a unified form of data and vice versa. Some problems have been found in the experiments with the previously implemented gateway. First, a bottleneck state might arise if a number of mobile devices request data synchronization simultaneously. Second, the gateway itself would become a serious vulnerable point to an attack during the process of converting received data. The proposed gateway can solve this bottleneck state and security issue since it converts data and processes synchronization request in a mobile device. In this paper, the proposed gateway is constructed and the results of some experiments with the gateway are presented. According to the results, the proposed gateway operates properly and it is relatively insensitive to the bottleneck state.