By Maggie Shiels
Technology reporter, BBC News, San Francisco
Analysts believe accurate voice search could boost Google's business
Google has said it sees voice search as a major opportunity for the company in building a presence on the mobile web.
The company's vice president of engineering made the comments during a wide-ranging discussion at the Web 2.0 Expo in San Francisco.
"We believe voice search is a new form of search and that it is core to our business," said Vic Gundotra.
SearchEngineLand editor Greg Sterling agreed: "If done right, it could be a valuable strategic feature for Google."
Mr Gundotra acknowledged to the audience that "voice recognition in the early days was a nice trick but not very usable".
There were early complaints that Google's offering could not understand accents other than American and that results were often garbled.
"Look how far we have come. I get the advantage of looking at daily voice queries coming in and it's amazing. It's working. It's reached a tipping point. It's growing and growing very, very fast and we are thrilled about it," said Mr Gundotra.
He declined to share figures about just how many queries the company deals with via voice search.
However, Mr Gundotra did say: "It's one of those technologies we think gets better with usage.
"We launched it on the iPhone and have seen a 15% jump in accuracy because, as more people use it, we collect more data and our accuracy gets better."
In 2002, Google Labs introduced a service that allowed users to search with a simple phone call. The company admitted it "wasn't very useful because the results were displayed on your computer and Google discontinued it".
Six years later, the search giant introduced an improved feature under the Google Mobile App for the iPhone.
Vic Gundotra says "voice search is core" to Google's future mobile plans
It is also available on the Android based T-Mobile G1 and last month was introduced on the BlackBerry as a free download. The New York Times's Gadgetwise blog rated the BlackBerry version the "App of the Week" earlier this week.
Early iterations that worked best with North American accents had problems understanding other accents, including British. BBC technology cCorrespondent Rory Cellan-Jones reported in November last year that his attempts to use it were "pure gibberish".
For example, his query about the next train, West Ealing to Paddington "delivered some useful information about 'neck strain' - but no train times".
Those problems have since been largely ironed out and Google said it was continuing to work on improving the accuracy of the service. This, Mr Sterling said, is crucial if the company wants it to give them the edge in the marketplace.
"My view is voice search could be a strategic differentiator if it works well. It depends on how much better Google's system is compared to, say, Yahoo's or Microsoft's.
"If they come up with a really great version that is really accurate, it could retain users and likely increase search usage for Google," said Mr Sterling.
At Web 2.0, Mr Gundotra also talked about a web-based version of Google's e-mail service, Gmail.
Google's "technical prototype", coming soon to the public
He demonstrated a "technical prototype" on the iPhone and the G1 and said "Stay tuned" for a release date.
Mr Gundotra said the prototype used HTML 5, an as-yet incomplete version of mark up language of the world wide web.
He revealed that Google would create a whole suite of offline apps using HTML 5 and that "we are going to be leaders in taking advantage of HTML 5".
Mr Gundotra also said that engineers were working hard to bring the Chrome browser to the Mac and that while there was no date for delivery, "we are making progress to get it out as fast as we can".
During a question and answer session, Mr Gundotra was quizzed on rumours circulating in the blogosphere that Google is looking to buy the micro-blogging service Twitter.
Google said "no comment" on rumours it may want to buy Twitter
"I'm a big fan of Twitter but we don't as a policy comment on rumour or speculation," he said.
Meanwhile, Twitter co-founder Biz Stone has said that he has been "flooded with requests for a response to the latest internet speculation about where Twitter is headed".
In a blog entitled Sometimes We Talk, Mr Stone wrote: "It should come as no surprise that Twitter engages in discussions with other companies regularly and on a variety of subjects.
"Our goal is to build a profitable, independent company and we're just getting started."