Yahoo unveils version 3.0 of its IntoNow social TV app

Looking to sieze control of the fast-emerging market for second-screen TV-watching apps, Yahoo (s YHOO) introduced late Monday a significantly tweaked version of IntoNow.

Available Monday evening, IntoNow 3.0 will allow users to caption and share screen shots from whatever it is they’re watching without having to photograph their screen. It has a novel music recognition feature that can ID tunes in shows, even if they’re not performed by their original artists.

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And it’s probably no coincidence that Yahoo chose to debut the upgrade during the Olympics. New syncing features bring up a flurry of content related to what’s being viewed at any given moment, whether it be medal counts or athlete bios.

“IntoNow 3.0 is born out of the behaviors we’re seeing,” said Adam Cahan, who founded IntoNow in early 2011 and sold it to Yahoo for around $30 million shortly thereafter. The company estimates that 80 percent of TV viewers are using a tablet or mobile phone while watching the tube now.

And IntoNow, which says that about 3 million users have downloaded its apps, has already worked with a number of the Fortune 500 brands who are looking to follow TV viewers onto the second screen.

One of the frequent second-screen behaviors IntoNow has observed, Cahan explains, is the tendency of users to photograph their TV screen and share those low-grade photos with friends on Facebook, Twitter and other social media platforms.

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IntoNow’s new CapIt feature delivers a steady stream of still images from the show or event the user is watching. Users can then choose a still image broadcast moments earlier, caption it any way they want, and share it with friends.

Meanwhile, Cahan is particularly proud of the new music-syncing feature. IntoNow is based on a science he calls “audio finger printing.” When you run the IntoNow app on your iOS or Android smart phone or tablet, it knows what you’re watching based on broadcast and cable audio feeds the company’s servers have scanned going back several years.

The app could always tell if you’re watching Monday’s episode of TNT’s The Closer. But it couldn’t identify, say, a popular song that was re-scored by studio musicians for a show, or music that was played in a snippet that was simply too short.

Meanwhile, the upgraded app is also designed to “surface” to the user’s screen content that relates to whatever they’re watching — polls, news stories, trivia, etc.

This, of course, fits in nicely to Yahoo’s ambitious Olympics coverage strategy, which is short on broadcast licensing but long on ancillary content.

In fact, after a recent meeting with new Yahoo CEO Marissa Mayer, Cahan and his team were urged to accelerate their launch plan for the upgrade.