“The Elements” – Will the line between “app” and “ebook” blur?

What publishers can and should learn from “The Elements” is a recent interview by Mac Slocum of Author Theodore Gray, who launched his interactive book on a variety of channels. There are some good lessons for potential eBook authors here on what it takes to tool up to the new level of interactivity and design expecations that are become pre-requisites to stand out in the rapidly growing interactive content market.