The phone is the first to use Google's operating system Android, which the company hopes to make open-source.
The handset has a 3.2 inch touch screen and slide-out qwerty keyboard. It also incorporates a compass, which together with a motion sensor allows users to navigate Google Maps by turning the phone.
The following is from Mike and Maaike:
The G1 is the first phone to run on Google's Android operating system.
Mike and Maaike worked with Google to envision a device that would run the open-source Android operating system, extending the functional utility, intelligence, and ease of the Google experience into a phone.
The device has been developed for production by HTC and is now offered by T-mobile as the G1.