A new app invites you to command your iPhone in the same way that Captain Kirk addressed the Enterprise’s computer.

Siri's visual interface displays a transcription of what you say, then hands the data off to an appropriate web service or search engine.

Siri’s visual interface displays a transcription of what you say, then hands the data off to an appropriate web service or search engine.

Siri, an artificial intelligence-based voice-recognition startup, launched an iPhone app incorporating its technology on Friday. With the app running, you can address requests to your phone verbally, asking it things like, “Will it rain today?” or “Where is a good place for pizza nearby?” and “I’d like a table for two at Il Fornaio tomorrow night at 7.” The Siri app parses the sound, interprets the request, and hands it off to an appropriate web service, such as OpenTable, Yelp, CitySearch, and so on. It displays the results onscreen as it goes, giving you a chance to correct or adjust your request via onscreen taps.

It’s the most sophisticated voice recognition to appear on a smartphone yet. While Google’s Nexus One offers voice transcription capabilities — so you can speak to enter text into a web form, for instance — the Nexus One doesn’t actually interpret what you’re saying.

The voice recognition and interpretation abilities built into Siri have their origins in artificial intelligence research at SRI, a legendary Silicon Valley R&D lab that was also the birthplace of the mouse and of the graphical user interface. Spun out of SRI in 2007, Siri garnered a lot of attention for its ambitious plans to develop a virtual personal assistant. Actually bringing the product to market has taken quite a bit longer than expected.

In a demo shown to Wired.com, Siri responded quickly to spoken requests, answering questions about restaurants, directions and the weather with relative ease. It’s well-integrated with about 20 different web information services, and Siri representatives say that their application programming interface will allow many others to connect in the future.

From our initial testing on an iPhone 3GS, the app was zippy and smooth. Siri understood broad requests like “Find Chinese food nearby” and more specific ones like “Find Nearest Chase bank.” Impressive, and much more efficient than searching for businesses in the Yelp iPhone app.

The Siri app is free, and the company says it has no plans to charge end-users; the goal is to make money from referring customers to services via affiliate fees.

Siri is available for download in the iTunes App Store. It requires an iPhone 3GS, because it relies on that phone’s faster processing power, but Siri representatives say a version compatible with the older iPhone 3G is in the works.

Siri Launches Voice-Powered iPhone ‘Assistant’ | Gadget Lab | Wired.com.