Most drivers know this experience. They’re en route somewhere when their smartphone map app starts pushing back their ETA. Soon, brake lights appear ahead as traffic slows to a crawl.

But how did the navigation app know about the traffic before the driver encountered it? Popular navigation apps like Google Maps, Apple Maps, and Waze use real-time location data from drivers’ phones to detect slowdowns and estimate traffic conditions.

Learn what’s happening and why the estimates aren’t always right.

On This Page

How Do Smartphone Map Apps Detect Traffic and Predict Delays?

How Accurate Are Google Maps, Apple Maps, and Waze Traffic Updates?

SOURCES

How Do Smartphone Map Apps Detect Traffic and Predict Delays?

Map apps combine location data from many phones to understand traffic conditions on the road. Google explains that it uses combined location data for this, and Waze says drivers share real-time information just by driving with the app open.…