Google uses map app customers as traffic reporters

No longer is Google Maps merely a tool for your cellphone. Now your cellphone is a tool for Google Maps.

The firm says it now has enough users that it can give a good picture of traffic conditions by tracking the movements of their cellphones. If a large number of cellphones are in the same area and moving at a slow pace, that’s a pretty good indication there’s a traffic jam. (Similar technology is already used by some traffic data firms through devices fitted to cars.)

The system only tracks movements once a user specifically notes they are on a car journey, meaning it won’t get confused by people parked at home, or pedestrians who’ve gathered in a crowd for an event.

Because of the added data, Google is now expanding its live traffic maps from major highways to key arterial routes such as state highways and major inner-city roads.

Clearly there will be some privacy concerns, so Google has made it possible to opt out of the program (see http://google.com/support/mobile/bin/answer.py?hl=en&answer=81875 for details.) However, it’s at a price: those who don’t agree to their data being gathered won’t be able to use the My Location feature which is pretty much key to using the maps for driving. Where Google does gather data, it will permanently delete any record of user’s start and end locations once their journey is complete.

The mapping system is automatically turned on for users of the Palm Pre and the MyTouch 3G phones, while users of other phones can install it. However, the firm isn’t collecting data from people using the system on iPhones, likely thanks to restrictions on companies other than Apple collecting GPS data from the handsets.

Google notes in its blog that people stuck in traffic might not only want to warn friends of jams, but to “tell your city government that they might want to change the timing of that traffic light at the highway on-ramp.” It doesn’t say if there are any plans to share the traffic data with local authorities in such situations, though it would be a great PR move to do so.