关键词：通讯设备;通勤铁路;导航系统;公共交通
摘 要：The objective of this project was to create a real-time, context-aware transit navigation system. The system integrates the route-planning and real-time tracking functionality provided by current systems into a single, real-time and context-aware application, combining a smartphone end-user device, such as the Apple iPhone, with a sophisticated back-end service. The completed navigation system supports unified real-time transit navigation, including walking, biking or handicapped access, across all three Chicago transit agencies: CTA buses and subway trains, Pace suburban buses, and Metra commuter rail. The back-end is built as a generic routing service, which can be used by any number of client applications. On the client side, an iPhone application has been created, with an attractive user interface and a wide selection of convenient features. The iPhone application has been published on the iTunes App store for public download. The app is downloaded by approx. 2,0003,000 users per month, and has received over 1,000 reviews, many of which are very positive