After powering second-screen, connected-TV experiences for other companies including DirecTV and Nintendo's TVii app, i.tv acquired TV check-in service GetGlue last year to pull those experiences together. Now, GetGlue is relaunching as tvtag, an advertising-supported, one-stop information and social network centered around television watching, full of information from broadcast partners, augmented in real time by a team of live curators and TV viewers. At launch, the reworked app is available only on the iPhone, but CEO Brad Pelo tells us a version for Android is due in a few days, with a web experience and iPad-ready version launching shortly after that. The i.TV app is sticking around for now, but will be updated in the future, while DirecTV and Nintendo are already lined up for integration with the new platform.

The check-in and sharing features -- and built-in user base -- from GetGlue remain, but it's the curated info that the company expects will separate it from other services. The "taglines" are built by more than 50 employees creating high-level tags for live TV (covering the majority of what viewers are watching, on any channel), which users then fill in with additional captures, comments and reactions. It's also why tvtag thinks users will choose to open this app over Twitter and Facebook while they're watching TV, with the ability to search info from sources like IMDb and Google, or add to the tagline with their own notes and doodles. Those taglines are available for browsing later for DVR viewing, but this experience is about live TV. For events like last weekend's Grammys or Pro Bowl, and the upcoming Super Bowl, it can push play-by-play updates, as well as constantly refreshed stats and field positions.

Other than the big social networks, competition to provide synced TV info on other screens like your phone, tablet or PC is fierce, with everyone from Google Now, Dijit's recent acquisition Miso and Yahoo's IntoNow offering similar features. IntoNow is one of the most similar, adding the ability to ID TV content via audio and a complete feed of images from live TV channels to the mix. tvtag is more than an app however, and since it can open up access as an SDK or API, we may see its features and content pop up in other apps and on other devices soon. Still, given the following GetGlue has been able to attract we expect to see plenty of tvtag shares popping up in our timelines -- we'll see if its exclusive information and tight TV-focused environment are enough to keep its audience coming back.