I had something similar happen--found out a small feature I wrote six years earlier was getting nearly 3 million page views a month from almost exclusively iPhone users. Still not sure how they all found it (if it was just search engines I can't imagine the usage would end up being 99% iPhone users considering it's not iPhone focused).
A mobile version of the Drudge Report. Before the days of modern smartphone browsers it was an especially frustrating site to visit and I wrote a scraper that reformatted out all the long lists of unchanging links. Didn't think about it (or use it much really--it was more of an academic exercise) and then years later realized it had gained [significant] popularity.
The news out of Japan has increased traffic. 140k page views yesterday and 3.4m in the last rolling month period according to Google Analytics.
So what are you going to do? The easy thing would be to just shut it off, but more amusing thing would be to make the news links nonsensical (ie go to Onion etc).
Of course, the best thing would be to get your own cut of the revenue.
Instead of cutting it off, can you just add some ads on the page? Many will probably complain, leave 1 star reviews, and stop using the app, but in the meantime you'll make some money off the app (even the free version).
Whatever ethical issues inherent in profiting off scraped content have already been bypassed by asking for money, though any issues with the law could be a bigger concern.
What's the app? This could all start to make a lot more sense... It uses my URL because the main URL has three columns and a lot of static links. Looks terrible. With mine you can just swipe down through all the new stuff.
