A free app for Android, by CTA TRANSIT.
Chicago Transit Tracker – CTA Realtime Tracking is an official CTA real-time bus and train tracking app for the city of Chicago. This free and simple to use app lets you find out exactly where the buses and trains are in real-time, even if you are at home, the office, shopping, or dining. You can also find out when the next bus or train is arriving at your stop, even if you are still at home, the office, shopping, or dining.
The best part of this app is that it is free and simple to use, so you don’t have to worry about any kind of additional costs.
This app works as a complete journey planner for you. It will tell you the best time to start your journey, the best time to get the bus or train, and the best time to get the train.