The problem with so many of the other sites I've found that offer books for kids to read on a handheld, is the fact that the books were written and produced for this purpose. Needless to say, the quality of many of the books designed as an app are not too great. PicPocket books offers mostly books that are already well reviewed by reviewers--books that kids already enjoy in book form.
I loved ROUND IS A MOONCAKE. The book is well done. You can choose to have it read to you and choose to have word highlighted as they are read. Picpocket doesn't have a huge selection of books yet, but the ones that they have are good.
I was pretty worried that picture books would never be good enough on a handheld--that ebooks were really about books for adults. But after seeing ROUND IS A MOONCAKE, I think I was wrong.
I am not sure how many of these books we'll want our kids to have on their iPod or how we balance this out for young readers. They are semi-expensive because you buy each one as its own app. Each costs a few dollars. But I think this is similar to listening centers and other ways kids have enjoyed books over the years. I can imagine kids having a copy of the "real" book and a copy of the ebook for trips, etc. I also think there are some good implications for the library and classroom if companies continue to put out quality books. As long as the book and story are good, I see it as a great thing for kids to do on their own. I am excited to see some great books like Grace Lin's becoming part of the world of handheld picture books. I am so happy to see PicPocket Books working toward getting quality books reformatted in this way.