Following some adjusted wording on iBooks Textbook pages inside of iTunes that ignited speculation of iBooks Textbooks finally becoming compatible with the iPhone, a new iBooks Textbooks category has begun populating on the iOS 7 App Store for iPhone. The section is currently accessible via the Education category of the store.

As you can see in the screenshots above and below, the category is not currently populated or fully functional. However, there is promotional imagery for several categories (including Life Sciences, Humanities, and a High School Core Curriculum) that is fully optimized for the size of the iPhone’s display…

While it is possible that this is simply a server error on Apple’s part (the iPad and iPhone obviously have the same iTunes backend), perhaps the optimized artwork is a hint that iBooks Textbooks support for the iPhone and iPod touch is imminent.

We’ve also just discovered that yesterday’s reference to all iOS devices supporting iBooks Textbooks has returned:

A leak of a future iTunes-related feature would not be unprecedented. Ahead of Apple’s October 2012 event, references to the then-upcoming iBooks 3.0 appeared in iTunes. Back in 2011, references to new iCloud app auto-updating features also surfaced prematurely.

Apple is holding an iPhone-focused media event on September 10th, so perhaps the potential announcement will occur on that stage.