As more and more TV shows and broadcasters create supporting apps, in the US at least the second-screen phenomenon is starting to become mainstream viewing behavior, especially among younger digital native viewers.

According to Parks Associates, 14 percent of US smartphone and tablet owners are already regular users of TV content apps and, despite the fact that this is a fairly new trend and an area where TV stations and program makers still aren't sure what users want, 75 percent of app users claim to be happy with the experience.

There's a growing number of TV content apps, offering different types of content and features, so what is proving the most popular? Parks Associates report "TV Channel and Network App Users" shows that watching video clips related to a TV show or its channel is the top activity but that consumers are also using the apps to play games built around TV content and to shop for merchandise related specifically to a TV show.

The research also finds that these apps are proving a huge hit with young adults. "Companies in the television industry are experimenting with several approaches to TV-related apps for mobile devices," said Brett Sappington, Director, Research, Parks Associates. "Some are already noting several benefits, including greater viewer immersion, the ability to appeal to viewers outside of the broadcast window, and new aspects to storytelling. However, the most important implication may be for advertising. As consumers increasingly tune into mobile devices during commercial breaks, these apps provide a way to keep viewer attention."

From the article, "Immersive viewing: second screen content hitting the spot."