Shares in sat-nav companies bombed today after internet giant Google upset their world with a free sat-nav tool for Android 2.0 mobile phones!

This new feature comes with everything you’d expect to find in a GPS navigation system, like 3D views, turn-by-turn voice guidance and automatic rerouting. But unlike most navigation systems, Google Maps Navigation was built from the ground up to take advantage of your phone’s internet connection, said Google engineers.

“When you use Google Maps Navigation, your phone automatically gets the most up-to-date maps and business listings from Google Maps — you never need to buy map upgrades or update your device,” said Keith Ito, software engineer at Google.

The software comes with a variety of views, such as Traffic View, where Google grabs traffic data over the internet, Satellite View and an amazing Street View feature that you activate by double-tapping your phone’s screen. The software also comes with a nifty “search by voice” function.

At the moment it’s only available in the US as a beta, but I can’t wait for it to come out over here, now I have my HTC Hero. What’s going to happen to the sat nav market (or even the iPhone, when the TomTom application for it costs around £60)?