A software system for police work is developed based on Android. The system consists of a client-end application running on Android mobile devices and a set of server-end service applications. The system components include database server, WEB server, wireless network and Android front-end. The Android end accesses the WEB and database services via China mobile wireless communication. The content of this paper covers the overall system structure design and detailed description of the analysis, design and implementation of the database and the basic police work application.