Media based app development which receives content automatically from Drupal feed

We have a media entertainment/news portal website done in Drupal. We also have a companion app which receives content manually from this website. Now we need to redesign this iOS and Android app which receives content from the the same website using a Drupal auto-feed, so that we don’t have to manually populate it. Our website content is images, videos, text, social posts and shoppable widgets. We are currently using ad network (some usage tracking system (Ommniture and Google) and some 3rd party ad networks in our existing mobile application. We would like to use the same in new one as well. Website content is updated very frequently and divided into various categories. Our mobile app should have those categories as well. We want a fluid user experience and smooth video playback, immersive pictures display with articles. Personalization is key such that we want to develop onboarding user flow allowing users to follow their favorite topics, and serve up personalized content feed also based on usage, Ideally you should use a middleware like Phonegap or Xamarin for this, so we can get iOS and Android builds, but if you prefer doing it 2 different native apps for each platform, we are also fine with that. You will need to have very solid knowledge of Drupal, as we can’t afford our site going down at all due to any plugin failure etc. So any change you need to make in our site in order to get feed working has to be tested & tried by you first on a test server. Application has to implement some local caching, so any article visited by user or pictures downloaded once remain for some time on local storage to avoid frequent network call & buffering.