Andy Rubin, Google director of mobile platforms, said, "Despite all of the very interesting speculation over the last few months, we are not announcing a Gphone.
"However, we think what we are announcing - the Open Handset Alliance and Android - is more significant and ambitious than a single phone."
Android is an open software platform for mobile devices. It includes an operating system, user-interface and applications - without any proprietary obstacles that have hindered mobile innovation, said Rubin.
Android has been developed in co-operation with the Open Handset Alliance, which consists of more than 30 technology and mobile leaders including Motorola, Qualcomm, HTC and T-Mobile.
"Through deep partnerships with carriers, device manufacturers, developers, and others, we hope to enable an open ecosystem for the mobile world by creating a standard, open mobile software platform," Rubin said.
"We see Android as an important part of our strategy of furthering Google's goal of providing access to information to users wherever they are," he said.
An Android software development kit will be available from Google later this year, and users will see the first Android-powered phones in the second half of next year, said Google.