In this paper, we discuss the design and implementation of a mobile object management system that makes use of the existing GSM (Global System for Mobile Communication) networks and it's extension- GPRS(General Packet Radio Service) for data communication. We use a novel Composite Communication Scheme (CCS), which uses SMS (Short Message Service) and GPRS to achieve reliable and economical communication between mobile objects and the control center. We also use Unified Data Management (UDM) for control center management, which significantly reduces the cost of maintaining separate data centers. We have deployed our services in two medium-sized cities with real users. The cost evaluation shows the high performance, usability and cost-effectiveness of this service in real production environment.