Is Building A News Social Network Within Its New iPhone App, the news service developed in The New York Times’ R&D labs and incubated at betaworks, is launching its iPhone app today.

A bit unusually, the part of the app that you’ll use first may actually be the least interesting. In some ways, the new app is just a redesign of what was already offering through its iPad and email products — a list of news stories, pulled from your Facebook and Twitter streams, then curated based on signals from Twitter and, and presented with the context of the initial tweet or Facebook comment.

I’ve played with the app, and as a straightforward, curated newsreading service, it’s already pretty useful. But it sounds like General Manager Jake Levine has bigger ambitions. The app includes a feature called Reactions, which Levine calls a “purpose-built social network” — in other words, a social network for sharing news and your reactions. You can post a reaction to the stories in your stream, then follow other users and comment on their shared stories too.

To make things easier, you don’t even have to come up with a smart remark of your own. Instead, you can just select one of five pre-written responses — “Ha!”, “Wow”, “Awesome”, “Sad”, and “Really?”

The hope, Levine says, is that users will download the iPhone app and immediately get use out of it through the curated news feed, then over time, build a smaller network of friends who they want to discuss the news with. Early users are already reporting that they feel more comfortable posting honest reactions in, rather than on Facebook and Twitter (Levine argues that the larger social networks have “evolved from conversational media to broadcast media.”)

Ultimately, it’s the Reactions social network that will be “defensible,” he says. has been working on the iPhone app for the past four months, and Levine says it’s the company’s first product since making some key hires, including designer Justin Van Slembrouck (who designed the Wired iPad app and the New York Times’ Times Reader app) and iOS developer Rob Haining (who developed Epicurious and the original GQ app). Although the company has been focused on the iPhone recently, and even though the iPad app has been less successful than the email digest, it sounds like Levine plans to add the new features to the iPad eventually.

You can download the app here.