Google officially entered the mobile-phone business Monday, pushing the development of a free software platform to compete with current cellphone operating systems.

As part of its entry, Google unveiled the Open Handset Alliance, a consortium of big-name companies pledged to help make mobile phones more open to developers through using the Linux operating system.

Beyond Google, the alliance includes T-Mobile, Sprint Nextel, China Mobile, Motorola, LG, Samsung, HTC, Intel, Nuance Communications and eBay.

The software platform — named Android — will compete directly with three leading mobile-phone operating systems: Symbian, partly owned by Nokia; Microsoft's Windows Mobile; and Research In Motion's BlackBerry.

As significant as the announcement may be, it fell short of what some were waiting to hear — that Google would launch a mobile phone called the Gphone.

"We aren't announcing a Google phone today," said Google Chairman and Chief Executive Eric Schmidt during a conference call. "What we are focusing on is the perfect platform if you were to build a Gphone. It's so open and has so many capabilities to build a phone or other device. ... It starts a whole wave of innovation."

The announcement targeted the behind-the-scenes workings of the wireless industry and served to inform developers about creating applications on a platform that bills itself as less restrictive than current popular systems.

The software specifications will be available starting Monday, but consumers won't likely see a phone until late 2008.

HTC, a Taiwan handset manufacturer with American headquarters in Bellevue, said it will launch an Android phone in the second half of 2008.

Schmidt and others gave few details about what Android would look like, but the alliance's Web site said devices built on the platform would personalize the phone's homescreen or designate their favorite photo application to view their photos.

From a developer's point of view, it would allow combining information from the Web with data on the phone, such as the user's contacts, calendar or location.

Google has been working on developing a mobile strategy for some time. In 2005, it purchased Android, a company started by Andy Rubin, now the director of Google's Mobile Platforms.

Rubin's background includes stints at Apple and Microsoft.

But he also was a founder of Danger, which built the Sidekick, a device sold by Bellevue-based T-Mobile USA that is popular with celebrities and teens because of its keyboard and easy messaging capabilities.

Cole Brodman, T-Mobile's chief development officer, said Monday it was because of Rubin that T-Mobile was chosen as an early partner in the Open Handset Alliance.

Rubin stayed in touch with T-Mobile after he left Danger. His presence at Google gave T-Mobile the opportunity to partner or invest in developing products.

"It was clear that it was going to be a good platform," Brodman said.

He said the Android platform will help carriers bring social networking, user-generated content and other Internet-driven services to the mobile phone.

He said carriers and handset makers who use the platform won't be limited to using Google services, such as maps, mail or even its ad network.

"It may be that a carrier will choose not to use them and bring something else to market, and that's OK, and that's the way we were thinking about it as well," he said.

Although Google and the alliance are backed by heavyweights, it may be difficult to bring about change.

Wireless carriers have been criticized for having closed networks that restrict applications that users can download.

The carriers reason that without the so-called "walled garden," they will become only a network provider and not able to sell more profitable services.

Another challenge is that developers may not want to build applications for yet another platform.

Scott Horn, general manager of Microsoft's mobile-communications business, said it took Microsoft five years for developers to build 18,000 mobile applications.

"Developers are rational people; they write applications where there's an opportunity for people to use or buy them," he said.

Still, IDC analyst Shiv Bakhshi thinks Android will have a disproportionate influence on the industry, much like Apple's iPhone. The iPhone has received much attention even though it sold about as many devices in one quarter — 1 million — as Nokia sells every day.

"I think it [Android] will do the same thing, even though it doesn't have a great market share," Bakhshi said.

"The balance of power between the operator and its device and application suppliers is being contested, and it's shifting anyway. This will add to that."

Tricia Duryee: 206-464-3283 or tduryee@seattletimes.com