Develop an iOS version of my existing Android APP

Basically: I need an iOS version of an available app I already have (Alerta Licitação), which is a customized RSS reader. It reads RSS feed from my website, according to user configuration. In free version, you can subscribe to a maximum of 2 FEEDS, and in premium version, 30. Android App has many functionalities, but those that MUST BE in iOS version are: 1) App reads each RSS feed each x minutes, and stores all articles in internal database; 2) Notifies user if there is a new article in each feed. 3) Has option to "FAVORITE" one article; 4) Has option to "SHARE" one article; 5) Is able to mark each article as "READ" or "NOT READ", and shows them differently to user. 6) Is able to show all FAVORITE articles from all feeds in one Activity (screen); 7) Is able to show all NOT READ articles from all feeds in one Activity; 8) Manually refresh feed content. Optional function: 8) Deletes from internal database those articles that are not shown anymore in FEED (it would be great to free internal memory) >>> FEED SUBSCRIPTION <<< User starts with NO FEED SUBSCRIPTION, therefore a FEED SUBSCRIPTION control (insert, delete) must also be done. 1) Inserting a feed is possible by: a) User chooses one of 27 pre-defined RSS FEEDS (which points to pre-defined URLs inside the app); b) User creates one of its own, by typing keywords of his choice (string, limited to 255), and gives a title to it. (if not given any title, app assumes the title is the same as keywords); c) User gives one integer (in APP it is called UASG), which will concatenate to an URL (for example: http://alerta/?uasg=number). Website creates a feed with this number; 2) Deleting the feed will delete all entries from internal database; >>> PREMIUM CONTENT CONTROL <<< Free account users can subscribe to a maximum of TWO feed. Premium account users can subscribe to a maximum of THIRTY. Therefore a SUBSCRIPTION control must be done. >>> ADVERTISING <<< No need to integrate with adMOB.