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Provides status and detailed information about events (both planned and unplanned) affecting service. Provides up-to-the-minute arrival predictions and location data about buses on the CTA system via the CTA Bus Tracker SM service. Provides up-to-the-minute arrival predictions about trains on the CTA system via the CTA Train Tracker SM service. Also, see our CTA Trademarks & You section to help understand what you can and can't do with CTA marks under this agreement.
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To use any of CTA’s APIs or data offerings in your own applications, you’ll need to agree to our Developer License Agreement and Terms of Use. We'll continually be working to improve the available tools and content, and we'd love to hear what you think. You can find information for each API for how to query for a JSON response in the documentation for each family of APIs. We've published JSON versions of our Train Tracker API, Bus Tracker API and Customer Alerts API endpoints! (Previously, all our feeds were only available in an XML format, only.) We also have a Customer Alerts API that is a feed of both planned and unplanned events that affect service, as published on. The information provided through data feeds includes static schedule and service data using an open standard, and APIs that can get you up-to-the-minute information from both CTA Bus Tracker SM and CTA Train Tracker SM. This set of data offerings will be able to help you create interesting new applications and mash-ups that’ll help people get the information they want or need about CTA services, wherever they want to receive it. We’re glad you’re interested in developing applications using data from CTA.
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