I am participating in two EVO sessions this year – “Crafting the ePerfect Textbook” and “Educators and Copyright: Do the Right Thing”.
For week 2 of the eText session, I have written up a short analysis of different things that can be included in eTexts, and how much of that is up to the author (as opposed to the software or machine presenting the eText). To illustrate some of the things authors can do with eTexts without even learning any programming or using apps or the such, I made five style sheets to control the layout for various situations (mobile, accessibility, printing, and the such).
The page is here. Warning: it is long.