Ebook reviews the safe way. Aaargh!

So what’s the big deal? two years ago, John Green wrote on his Tumblr that hundreds of people send him notes to say they illegally downloaded one of his books, “as if they expect me to reply with my hearty congratulations that they are technologically sophisticated enough to use Google or whatever.”

Piracy is a growing problem. How do unauthorized digital copies of books end up being shared? The short answer: easily. Before J.K. Rowling’s Pottermore began releasing e-versions of the Harry Pott...