Turn-by-turn navigation poses a headache for expensive rivals.
The rumours were bang on: Google was working on a free mobile navigation application. It's been unveiled today, and is called Google Maps Navigation.
It's part of the also-unveiled-today Android 2.0 platform, which will be first seen on Motorola's new Droid handset which was, yes, unveiled today.
As the name implies, it blends turn-by-turn navigation with Google Maps, adding in voice search, satellite views, Street View, live traffic data, and a special mode for when the handset is placed in a car dock.
But the most important feature? It's free.
That's a significant challenge for standalone in-car GPS devices, but an even bigger headache for rival mobile navigation applications - many of which are currently selling for more than £50 or charging monthly subscription fees.
Article continues belowAdvertisement
How big a headache? Garmin's shares are down 16% since the announcement, while TomTom's have fallen 21%.
The app is initially available on Android 2.0 handsets only, although CNET reports Google as saying it's working with Apple to launch the app for iPhone, and may license the technology to GPS device makers too.
A video demo of the new service is embedded below:
