I'm not sure about apps on the app store, but I know Amazon has this capability with kindle books, which they've used in the past: http://www.nytimes.com/2009/

I'm not sure about apps on the app store, but I know Amazon has this capability with kindle books, which they've used in the past: http://www.nytimes.com/2009/07/18/technology/companies/18amazon.html http://www.nytimes.com/2009/07/18/technology/companies/18ama... The book in question? 1984.