Google on Thursday will begin expanding the instant-messaging feature built into Gmail so people can use it to send text messages to their contacts' phones.
To use the feature, people can click on a chat window's settings to send a text message with SMS or type a contact's phone number in the chat contact search box, Gmail Product Manager Keith Coleman said in an interview. The feature is experimental, available only to those who opt to use it through the Gmail Labs settings, and Google will begin offering it Thursday.
Gmail Labs has let Google offer a wide variety of experimental features to those who want them--27 so far since the feature launched in June. None has graduated to full-fledged features or options, but Google clearly is eyeing candidates.
Among the most popular Gmail Labs features, according to Coleman: a reminder that makes sure you really have attached an attachment you promised; "Superstars" that let people flag messages not just with yellow stars but with a variety of other colors; pictures in chat to show the face of your instant-messaging contact; and QuickLinks that let people bookmark Gmail interactions such as a search for all unread messages from your mother.
However, Google still has interface refinement and testing work to do before any feature becomes part of the standard Gmail application, Coleman said. Gmail Labs is intended to be a proving ground where new features can be tried sooner rather than later, even if they're still immature.
However, Gmail Labs is limited to Gmail. The Gmail text-messaging feature doesn't work with Google's other instant-messaging options, including the chat gadget that can run on iGoogle or the Google Talk software that can be downloaded and installed on a computer.
Behind the scenes, Gmail Chat sends text messages to people's phones from a specific Google phone number--one of about 1,000 the company reserved for the purpose--and each pair of people communicating gets to keep that number for future use. That's handy, Coleman said, because the person who receives the text message can store the Google phone number in his or her address book as a conduit to reach the sender's computer-based Google chat.
The phone numbers are recycled, Coleman said; the system works because each person probably won't need more than 1,000 text-message chat contacts.