Read Aloud iBooks
iBooks supports much more interactivity than other ePub readers. Bear Legend is taking advantage of all that iBooks has to offer, particularly it’s “Read Aloud” feature. The “Read Aloud” feature highlights EVERY word as it is spoken by the narrator. Highlighting each word as the narration is heard make Bear Legend a true piece of learning material. Through the visual cues a young reader learns to associate the written word with the spoken word.
Too see apples description of the feature http://www.apple.com/itunes/inside-itunes/2011/06/ibooks-13-includes-new-read-aloud-feature-for-childrens-books.html
UPDATE: Apple now categorizes books with this feature under READ & LISTEN in the iBookstore. However very few books besides the Bear Legend Series are set up to highlight EVERY word.
Visit the iBookstore READ & LISTEN CATEGORY