A recent project requirement involved sharing of news article content between our public websites and a Xamarin app (which consumes Sitecore content through an API). Our article content, stored as Rich Text, can contain markup which does not translate well to a mobile app. To resolve, we introduced a new field to store the sanitized markup, updated during the item saving event handler. Below is the implementation. Fortis is used as the item wrappring library.
Wiring up via patch:
Note the event disabler to prevent the item saving event handler from being called repeatedly during the end edit of the item. Other approaches to consier involve updating content on the save event in the Rich Text field itself.