+1 from the app store reviews:

This is a great app. I’m using it daily in my free time to learn. The bookmarking ability is very useful. What I found a bit annoying is that the “Categories” that show up in the bottom of desktop version of articles are excluded in the app version. I really like those because they give me a way to explore other pages/articles in the same category. Hope they add them to the app version.

+1 user through the iOS support email:

"Good morning,
I was wondering if you could add the ability to view categories to your roadmap items for the iOS app?
Categories are a very important part of how you use Wikipedia, and I find myself using the mobile app more and more as time goes on."

+1 user through the app store reviews:

Just wondered why it’s not possible to view which categories an article belongs to (like it is on the desktop version)

+1 user through the support emails:
Hallo Wikimedia Team,

First of all thank you for keeping Wikipedia free.

Here is a suggestion that i would like to make.
In Wikipedia app, it possible to sort articles in different categories so that i get to see the top read articles if i select one particular category.
So let say out of 100s of different categories i select Country then i get the suggestion of top read articles on the countries and so on.