Voice-activated search is an ancient idea in the sci-fi world of the future, where crew members on Star Trek asked the computer questions. But only now is true voice search making its way onto mobile phones, allowing people to do more than just ask their phones to "call Mom."

VoiceSignal Technologies Inc. in Woburn and Nuance Communications Inc. in Burlington have both developed software platforms that will provide voice-enabled mobile search and display results on the phone screen. Search giant Google Inc. dipped its toe into the directory assistance business earlier this month with a free 411 service that also offers to send users a text message answering their verbal query. In March, Microsoft Corp. said it would acquire leading voice service provider Tellme Networks Inc.

The building interest in such services promises that consumers soon will be able to use their mobile devices to find a pizza parlor in their vicinity and then get a list of options on their phone screen and a map without having to take their hands off the steering wheel.

"Speech in general has been that technology that's always right around the corner. And we've clearly, over the last couple of years, turned that corner," said Jeff Van Rhee , a senior analyst at Craig-Hallum Capital Group in Minneapolis. "Now we're just getting into the handset, where there's really value added."

To date, mobile voice-enabled search has been restricted almost entirely to basic directory assistance -- a business worth about $4.1 billion a year, according to Dan Miller , senior analyst at Opus Research in San Francisco. , Miller projects that by 2010 the market will expand beyond 411 services and grow to $7.2 billion, as people begin to ask their phones to do everything from finding the nearest gas station to locating friends who are nearby.

"These are applications people are very familiar with," Miller said. They just haven't had the opportunity to use their voices to access them by asking their phone.

Cellphone carriers see that familiarity as an opportunity to sell pricey data services to their customers. Wireless carriers have been spending billions on their wireless networks, anticipating the day when people would truly begin to treat their phones like portable computers -- searching and buying ringtones or songs, writing e-mails and instant messages, and surfing the mobile Web.

VoiceSignal and Nuance Communications are looking to capitalize on the most intuitive method of searching -- asking.

The pop culture implications of the technology aren't lost on the developers who toil on the programs, testing them in sound labs to ensure that the ums and ahs that pepper human speech do not disrupt their functionality.

"You don't want it to be too HAL-like," said Peter Mahoney of Nuance, referencing "2001: A Space Odyssey." "You don't want your speech system telling you the decision you made is a bad one."

VoiceSignal, a company with speech-recognition technology on 140 million phones, has developed VSearch, a service that can plumb the depths of a song catalogue, find nearby businesses, or help people with directions.

To use the local search, people press a button, say what kind of business they are looking for, and where, and receive a list.

The results are displayed on the screen like the results from any Internet search engine, and people can click on a business to find a map or contact information. As on the Internet, the service is supported by advertising and is free to the user, aside from the cost to access the data services.

The service will become available in Europe this year and is being tested with US carriers, and will ultimately include features like weather, movie times, stock quotes, horoscopes, and sports scores.

"Most people have absolutely no idea how to use their [cellphone] Web browers to get information," said Daniel Roth , president of VoiceSignal. Voice search "turns the average user into someone who is using the Web on their phone, discovering stuff by mobile."

Nuance , a leading provider of speech applications in areas ranging from medical dictation to traditional 411 services, made its mobile search available to carriers this year, but none have made it available to their customers. The search service includes local search and song components, similar to VSearch.

But the company, which has powered voice-search and -recognition technologies for years in other applications, also offers a range of other solutions. Nuance Mobile Dictation, available later this year, will allow people to dictate e-mails to their smartphone, sparing their thumbs. The company's Voice Control, available on Sprint, allows people to access the full functionality of their phone without scrolling through menus.

During a recent demonstration, Mahoney said "weather 02459" into his device and got a forecast of light rain in Newton , and said "top stories" to get USA Today's top stories.

Nuance and VoiceSignal, who both say that mobile represents the fastest growing sector of their businesses, are currently battling over patent issues, even as big technology players like Google and Microsoft begin to move into the market.

Google's offerings signal a shift into voice-based search , and Microsoft chief executive Steve Ballmer said that the deal to buy Tellme Networks "will enable us to deliver a new wave of products and revolutionize human-computer interaction." Yahoo Inc. has recruited speech expertise in house, according to Van Rhee.

"This is just the tip of the iceberg," he said. "They'll go much further because they want to own your search experience on the handset."

Carolyn Y. Johnson can be reached at cjohnson@globe.com.
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