It has been a long time since I was a young adult and my interest now is mostly based on a desire to write something in this genre. I am, however, very well versed in the dystopian genre. Admittedly, I am just estimating (rather than knowing) what young people like, but it seems to me that they will enjoy this book, especially those in the 12-16 category.
Two things kept me turning pages, the characters and the mysteries. As other reviewers have already said, the characters are likable and I really wanted to find out what happened to them. Also, the book has lots of secrets which are revealed gradually. I like that. (I don't give spoilers so don't expect me to tell what those secrets are.)
The world of the story is well-drawn. It has a nice balance of similarities and differences to our world. Overall, I believe this will do well with its target audience.
(review of free book)