The G1 -- unveiled in New York last month -- has been released exclusively by T-Mobile and will go head to head with products such as Apple's iPhone, the Blackberry and other smartphones from makers including Nokia.
The handset uses Google's Android software and is being touted as a phone with the capability of a hand-held computer.
The arrival of Android signals the opening round of the battle between Google and its rivals such as Apple to create software for the next generation of mobile phones that allows users to connect seamlessly to the internet.
It provides access to Android Market, which lets third party companies offer applications to users.
The G1 makes use of applications such as Google Maps, instant messaging through Google Talk, as well as high-speed internet browsing and a 3-megapixel camera.
Other manufacturers -- including LG and Samsung -- are expected to produce their own Google phones over the next 12 months.
Analysts have said the gadget could potentially transform the mobile telephone market by providing service supported by advertising instead of subscription fees. But some believe the phone may struggle to compete with the iPhone in particular.
Ernest Doku, from mobile phone comparison Web site Omio.com, told the British Press Association: "Despite the popularity of the Google brand, the G1's design lacks the inherent 'cool' factor that made the iPhone 3G such a mass market success for Apple.
"The launch of the G1 is important not only because it's Google's first foray into the mobile market but because it's also the launch of an entirely new mobile phone operating system.
"Android is the equivalent of releasing an alternative to Microsoft's Windows - and equally as risky."
However T-Mobile UK managing director Jim Hyde told PA that the phone was set to "revolutionise the way we use the internet on our mobiles."