In this chapter, we will create an app which will be able to fetch, process, and show the user several RSS feeds. RSS is a web feed, which allows users to access updates to online content in a standardized and computer-readable format. They are normally used in news websites, news aggregators, forums, and blogs to represent updated content and it fits very well to the mobile world, as we can have all the content from different blogs or newspapers just by entering the feed's URL in one app.
An RSS feed reader will serve as an example on how to fetch external data, store it, and display it to the user, but at the same time, will add a bit of complexity to our state tree; we will need to store and manage lists of feeds, entries, and posts. On top of that, we will introduce MobX as a library to manage all those state models and update our views...