Hello,
I am confident that I can help you with your app. I have already completed an iPhone app that had some RSS feeds based on categories. Also, the content of the feed was viewed within the app, and the user was not redirected to a web page. I can do the same for your application. It will be very easy for you to change the links to the rss feeds.
I would have one or two suggestions to make to your requirements, that I think would be some small improvements.
Thank you and looking forward to working with you!