We have Content Filter on the web version. And it's coming to the mobile app very soon. We're working towards having complete feature parity with the web app.
Strange, I couldn't find anything in the settings (iOS version). So maybe there's a divergent feature set and updates are forthcoming.
I can't speak to any of the apps, but after making my original comment, I checked out the website version, and the settings there do indeed have filters for category as well as specific terms.
Can verify. Settings > Content Filter > Custom Keywords. You can choose whether to hide the stories completely or blur them instead.