Barnes & Noble has expanded its children's reading library to the iPad, offering a free app called Nook Kids now available on the App Store. The app offers over 100 new interactive kids' books drawn from the larger library of children's offerings available on the Nook Color. The company says they will eventually offer over 12,000 children's chapter books in the Nook Kids app, which complements the regular Nook for iPad app that offers adults and older kids over two million digital titles.