INRIX® Traffic! available on App Store

INRIX Traffic! is a community-powered traffic application for iPhone and iPod touch that uses real-time, crowd-sourced information from more than one million vehicles to show current and predicted traffic conditions for freeways and highways in 126 cities in the US and Canada, as well as all interstates between metropolitan areas.
INRIX Traffic! also provides details on local traffic incidents and events.
Supplementing INRIX's network of GPS-enabled commercial and consumer vehicles, every INRIX Traffic! user sends anonymous GPS probe data to INRIX servers, which intelligently combine the information with billions of real-time speed data points from other drivers in the INRIX Smart Driver Network and road sensor information from departments of transport across the country.
Billions of data points enable INRIX to continuously and instantaneously update the traffic maps.
INRIX's predictive technology analyses commonly known traffic-impacting factors such as current traffic conditions, day of the week, season, holidays and related days, current and forecast weather, accidents and road construction, as well as other events such as school schedules, sports games and concerts, and even local variables such as the legislative calendar in Washington DC or the convention schedule in Las Vegas.