The interactive video start-up co-founded by former TechCrunch editor Erick Schonfeld is getting closer to premium broadcast customers by introducing a multi-camera capability.

TouchCast is a tablet video editing application that lets producers add interactive elements like photos, text, articles and web pages inside playing videos.

Revealing new features, TouchCast product manager Charley Miller tells Beet.TV it now supports “running external cameras in to the iPad so they can shoot on a really nice camera and get the depth-of-field that they are used to, making beautiful video but use TouchCast as a video mixer”.

One of those cameras, however, can be an iPhone. Miller shows how iOS devices can be used not just to produce but to input video in for inclusion in TouchCasts. Wall Street Journal is already beginning to use the functionalities.

We interviewed Miller at the NAB Show. Beet.TV’s coverage of the show was sponsored by Akamai.  Please find more coverage from Las Vegas here.