Have a look at some of my favorite and most creative digital children's literature I came across during my research. The Fantastic Flying Books of Mr. Morris Lessmore were originally produced as animation features, but work fantastically well trnasformed into an interactive children's story.
The Fantastic Flying Books of
Mr. Morris Lessmore
(Moonbot Studios LA, 2011)
Alice in Wonderland is one of the first releases in terms of iPad applications and remains one of the best and visually striking in my opinion.
Alice for the iPad (Atomic
Antelope, 2010)
Grimm's Rapunzel is one of the few 3D interactive Pop-Up Books I came across and has a nice children's friendly vibe to it with it's colourful and contrast high visuals.
Grimm's Rapunzel - 3D Interactive Pop-up
Book (StoryToys Entertainment Limited, 2013)
And lastly I selected the Tale of Peter Rabbit for it's clean digital adaptation. It very much upholds the feel and character of the original book and proves that simple and clean can also be a great goal to aim for.
PopOut! The Tale of Peter Rabbit (Loud Crow
Interactive Inc., 2011)