In a keynote address delivered to a crowd of developers in San Francisco, Google engineering director David Singleton unveiled the Android Wear smart watch technology.

The watch has messaging and phone capabilities, and it also plays music. Singleton’s demo, using a watch face designed by LG to run the Android Wear software, showed off the product’s “always-on display,” which shows a clock and a small tab with important information, in this case info for an upcoming flight. Users can also swipe the watch face to access more information tabs, or they can issue voice commands to take notes, set reminders or to start playing music.

The smart watches will also sync with the Google Play app store to download apps, allowing users to perform such tasks as ordering food or looking up directions from their wrist. The water-resistant watches can even detect when the wearer is physically active and it will automatically display a heart rate, something Google (GOOG) will likely tie in to its expected announcement of a health and fitness tracking service called Google Fit.

Singleton showed off several hardware options for the watches, designed by LG, Samsung and Motorola, which feature either square or round watch faces. He told the crowd that the LG G version will be available to order later today, as will the Samsung Gear Live watch. Another version, the Motorola 360, is the only of the first three iterations to feature a round shape and it will be available later this year.