I can think of one legitimate reason why a news website might choose to make an app instead of just making a good mobile website that everyone can use.

I was reading this article and the comments and both sides had great points. http://www.bothsidesofthetable.com/2...r-your-health/

Micropayments.

But anyway there's little information about what the BBC News app does so the whole whether it should be an app or a mobile website can't be discussed until someone actually tries it, or we know more about it.