A Simple App Helps You Avoid Red Lights, Saving Gas and Emissions

Using a network of smartphones mounted on car dashboards to help avoid stopping, SignalGuru can keep drivers from idling, the most fuel consuming–and frustrating–part of driving. Traffic lights are a necessary nuisance, but they’re also incredibly bad for the environment. Idling vehicles in backed up traffic soak up fuel, and are a source of needless emissions

More here:
A Simple App Helps You Avoid Red Lights, Saving Gas and Emissions