Apple's dulcet-voiced, speech-controlled personal assistant, a key factor in making the iPhone 4S a blockbuster, has breathed new life into the once-obscure and oft-maligned world of speech-recognition technology.

Siri, which can do everything from taking dictation for text messages and entering calendar appointments to answering general-knowledge questions, has intrigued users. Experts say it demonstrated emphatically that voice recognition has moved beyond the days of misheard commands, narrowly defined keywords and anguishingly slow speeds.

The smartphone industry is now scrambling to match and better Apple's offering. Google Inc and Microsoft Corp will likely want to cash in on an explosion of interest in an area they have invested in for years, without getting anything like the attention Siri is attracting.

"All the mobile phone manufacturers are investing in speech, expanding investments in speech, creating more elegant designs and integrating it more deeply into phones," said Michael Thompson, senior vice president for mobile at voice-recognition specialist Nuance.

Thompson was coy about his company's future plans but said he expects voice to be a central topic at the Consumer Electronics Show in Las Vegas as device makers jostle for attention from investors, media and consumers.

While voice is expected to be used in many areas of consumer electronics, the technology is particularly pertinent to cellphones because it simplifies functions from Web surfing to typing.

Internet merchants like eBay are also jumping on the bandwagon. And reports have emerged about a voice-control for TVS from South Korea's LG Electronics just before CES, which will open its doors in Las Vegas this week.

Many companies at CES are not yet ready to showcase products that can match or outdo Siri, Forrester Research analyst Charles Golvin said. But he said he expects the current flurry of activity to result in big voice product advancements in coming years as the technology is perfected.

Apple's rivals are planning to ship phones with improved speech technology in the fall, in time for the 2012 year-end holiday season, said Thompson at Nuance, which supplies and licenses technology to Apple but has its own voice app.

Even traditional PC makers will jump on the bandwagon: Intel announced at CES on Monday it will adopt Nuance's "Dragon NaturallySpeaking" voice-command technology on ultra-thin laptops -- dubbed UltraBooks -- coming out this year from the likes of Dell and Hewlett Packard.

"Voice as an input mechanism is going to be more and more useful and more and more prevalent," Golvin said. "Consumers have a lot of bad historical experience with it. They are going to encounter good voice interfaces more and more."

BANDWAGON ROLLS ON

Experts say the technology will evolve as more consumers get acclimated to it.

The interest in voice is already sparking acquisitions, with Nuance setting its sights on phones based on Google's Android operating system. Last month, it bought Vlingo, a developer of voice-control apps for a phones based on Android.

Android phone manufacturers -- all major rivals of Apple -- include Samsung Electronics Co Ltd, HTC Corp and Motorola Mobility, which Google is buying.

In the meantime, some developers are helping phone makers bridge the gap. A new app called "Ask Ziggy," launched a few weeks ago on Microsoft Windows-based smartphones, is generating buzz among users as it allows them to update Facebook, Twitter, answer texts and questions -- all through speech.

The free app helps a Windows phone mimic Siri's features and is already one of the top downloaded apps in its category.

"There's been a lot of interest globally," said Ask Ziggy developer Shai Leib, who told Reuters his inbox has been flooded with feedback from users, some even from Microsoft employees.

Leib plans to incorporate speech technology further in the app, to make phones completely hands-free. Microsoft's gesture-based Xbox Kinect gaming system has also raised the possibility of using hand gestures to manipulate screens and execute commands -- the so-called "Minority Report" interface named after the Tom Cruise sci-fi vehicle.

"With the success of the Microsoft Kinect and Apple's Siri, new ways to interface with CE devices have suddenly become top of mind," Ben Arnold, NPD's director of industry analysis, wrote in a blogpost last week. "I expect several companies to exhibit products using some of these new interface methods in an effort to differentiate themselves."

Leib argues there's nothing to stop smartphones also adopting gesture-recognition.

"The next level is to improve the speech, grammar and make the answers a little bit more conversational," he said. "The possibilities are amazing, especially with Kinect."

"I am looking forward to see what's going to happen with Windows 8 and if there are going to be future updates on the Windows phone that can recognize gestures."

HISTORY OF SPEECH

Apple was not the first to incorporate speech on phones. Google has had speech-recognition applications for Android smartphones for more than two years, and is now possibly trying to beef up its capabilities through the recent acquisition of a company called Alfred.

Alfred uses artificial-intelligence technology to sift through the Web's vast trove of data and recommend restaurants, bars and other real-world places users might like. Some experts say the technology could provide an important building-block that Google could pair with existing voice-recognition technology to create its own answer to Siri.

E-commerce companies are also playing catch-up, not wanting to be caught flat-footed should consumers become more comfortable using voice to search the Web and shop online.

EBay is planning a voice and image-based search function for its online market and "Red Laser" price-checking mobile software.

EBay Chief Executive John Donahoe has said he believes Siri is just the beginning, and sees a future where users can speak their preferences into phones to narrow down shopping choices.

Dan Miller of San Francisco-based Opus Research agrees. He was particularly intrigued by reports last November of an acquisition by Amazon.com of Yap, whose software coverts voice to text.

"The clock is ticking. In the next year or year and half expect a talking Kindle that supports commerce," Miller said.

Miller, who has studied voice technology for about 25 years, said he is gratified by the sudden spotlight on voice as he recalls years of consumer frustration over automated customer service systems.

"We're really happy to see this much positive attention," he said, "As opposed to "Oh the machine doesn't understand me."

(Reporting By Poornima Gupta and Sinead Carew; Editing by Edwin Chan and Steve Orlofsky)

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