This app was mentioned in 3 comments, with an average of 2.33 upvotes
You might enjoy the EnLighten app. It helps you optimize your speed to time the lights.
https://play.google.com/store/apps/details?id=com.otsys.notifier&hl=en
If you're asking my opinion on it now, it's much smoother and noticeably less buggy. I really like the addition of the speedometer and speed limits. I wish it could implement the features for enLighten as it would make a nice header widget for the main screen.
If you just want it on your phone because you dont have 140K to blow on that sexy beast:
https://play.google.com/store/apps/details?id=com.otsys.notifier
https://itunes.apple.com/us/app/green-driver/id695298744?mt=8
Edit: Coverage is limited: https://connectedsignals.com/images/coverage.png