Google Inc. today lifted the requirement that users must have an invitation to access its Google Voice telephony management application.
Google currently claims that Google Voice has about 1 million subscribers.
One of Google Voice's primary features is that it uses a single phone number that, when dialed, rings multiple lines belonging to a subscriber, such as his home, office and cellular phones. Google Voice also offers a voice mail message transcription tool, free calls to the U.S. and Canada, low international calling rates, conference calling capability and a central, Web-based voice mail in-box.
A subset of Google Voice features can also be used by people who don't want to get the single Google "phone number for life" and would rather use one of their existing lines.
"We're proud of the progress we've made with Google Voice over the last few years, and we're still just scratching the surface of what's possible when you combine your regular phone service with the latest Web technology," wrote Google Voice product managers Craig Walker and Vincent Paquet in an official blog post.
Google acquired the core Google Voice technology in 2007, when it bought a company called GrandCentral. At the time, Google stopped allowing new subscribers to sign up for the GrandCentral service. In March of last year, it reintroduced the service with a new name, Google Voice, and new features and made it available by invitation only.
Last year, the telephony service was at the center of a nasty dispute when Apple Inc. rejected Google's Voice application for the iPhone, saying that it duplicated native iPhone capabilities.
Google cried foul, characterizing Apple's move as unfair, but months later it found a way around Apple's block by releasing a version of the Voice application for mobile browsers.
Google and Apple are former corporate "best friends forever" now turned rivals, as they compete in more and more markets, such as mobile platforms (Google's Android vs. iPhone), online advertising services (Apple's iAd vs. Google's AdWords), Web browsers (Apple's Safari vs. Google Chrome) and PC operating systems (Mac OS vs. Google Chrome OS).
Google Voice also drew unwanted attention last year when transcripts of some of its users' voice mail messages showed up in search results. Google soon modified the application so that users can continue to share these transcripts on public Web pages, while keeping them out of the reach of search engine crawlers.