Users need to download and install a free application on their mobile phones using a mobile data connection. The maps are sent to the device over a wireless data connection.
The application is written in Java and requires a Java-enabled phone. A full list of compatible phones is available on Google's website.
The service is available to subscribers of selected US carriers only, and to all colour BlackBerry devices.
Google previously offered only text-based route information that was sent to the users by SMS.
The service does not incorporate live traffic information and does not support GPS navigation.
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