Any SIM Card

The Dev Phone can use any GSM carrier's SIM card, and the unlocked bootloader will work with custom Android builds as developers try out new applications. Google noted that the bootloader in the Dev Phone is different from the retail G1, allowing a developer to access handset features with custom builds.

Any SIM card from any GSM provider worldwide can be used, enabling development in countries where T-Mobile's G1 is not offered.

The Dev Phone is available for $399, but only to registered Android developers. There's a limit of one device for each developer account, and Google noted that it's not intended for end users.

Avi Greengart, an analyst with industry research firm Current Analysis, noted that the release of an unlocked device for developers is a fairly standard practice, but added he "certainly hopes" we will see unlocked Android devices for the consumer market.

"That's part of the whole premise" of the Android open-source platform, he said. He expects some Android devices will be customized for wireless carriers and some will be unlocked and available on the open market.

Sales Projections

T-Mobile is the largest of two companies offering an Android device, with the other Kogan Technology. Last week, Kogan announced the availability of its Android-based Agora and Agora Pro mobile phones for the Australian market.

The G1 from T-Mobile has had a strong reception in the marketplace, according to the company. New third-party applications are being released, and sales projections keep increasing. For instance, Peter Chou, CEO of G1 maker HTC, last month upped his sales projections to a million units by the end of this year. His previous prediction had been 600,000 units.

Some observers have suggested that the G1's appeal derives at least in part because it offers a high-end touchscreen with Google for T-Mobile customers, who are hungry for such a device. Others have pointed to the growing number of third-party free and inexpensive applications, and the appeal of what might become a vast ecosystem for the mobile device comparable to that for desktop and laptop computers.

An unlocked, robust Android device for consumer or business markets would test those theories. Will the device have appeal when it can work on multiple carriers, and consumers can take their pick of networks? And will making it consumer-adaptable to various carriers increase its attractiveness for third-party developers when the platform -- as well as the competitive environment -- increases exponentially?