Yes, you can do that. Where it gets tricky is that not all of the third-party apps—and it would be third-party apps that are creating the newspaper app, The New York Times, for example—implement all of the accessibility APIs, or application program interface protocols or rules, that Apple has set out. Not all of them work within them, so they can end up creating inaccessibility where, if they had just used the tools that Apple had given them to make an accessible app, there would have been accessibility.
On February 27th, 2012. See this statement in context.