The CTA Bus Tracker API provides a gateway into near-real-time CTA bus locations and estimated arrival times. Developers can use the official CTA Bus Tracker service via Web or mobile device. The API allows developers to get specific information from Bus Tracker to incorporate estimated arrivals and location information into apps. Data exposed via the API includes vehicle locations, route data, prediction data and service bulletins. The API uses RESTful calls and responses are formatted in XML.