About 40% of US consumers use their smartphones while watching TV, but they’re often emailing or posting on Facebook rather than interacting with TV shows on their phone, says Jason Forbes, Managing Director of Zeebox, a second-screen app, at the Beet.TV executive retreat earlier this month. He spoke with Lisa Hsia, Executive VP Digital Media at Bravo, a Zeebox partner, at the event.

“We give consumers a reason to engage with the TV,” he says, referring to the second-screen app. He adds that the average Zeebox engagement is 30 minutes per session.

The Zeebox service ties into social media, but it also includes e-commerce and discovery features, as well as interactivity. That could include viewing parties or live chats, for example, he says. “Social is one part, but you might not be into what your friends are watching, so we also find communities based on what you like,” he explains. Zeebox works with programming partners and advertisers to synchronize ads across the app and the TV screen. That could include watching a car commercial and signing up for a test drive using the app.

Zeebox is gearing up for the pending TV upfront and pitching synchronized ad packages to programmers, such as ecommerce tie-ins that enable viewers to buy products seen in a show. “Our data suggests 15% of consumers want to buy what they’ve seen,” he says.