Categories are (recently) visible in Mobile Wikipedia. In order to harmonise the experience of Desktop and Mobile Editors, editing categories should be possible in Mobile Visual Edit Mode. Currently it is only possible in Source edit mode, which is error prone and doesn’t make use of Cat-Wizard or other helpful UI.
I created this feature request from a larger discussion at Meta discussion about Mobile editing experience: https://meta.wikimedia.org/wiki/Talk:Wikimedia_Foundation_Annual_Plan/2023-2024/Draft/Product_%26_Technology#c-Shushugah-20230410184300-DLynch_(WMF)-20230403152500