Category tags are required on thrill posts because the ThrillPiXx "engine" is built off discovering thrills using certain categories. Categories are used to browse thrills and can also be subscribed to, allowing you to see all posts tagged with that category.
If you don't see a category that matches your thrill, you can choose the Other category. The Other category automatically displays if you search for a category that does not exist in the database.
If you don't see a matching category, but you'd like to have it, include a hashtag with the category you'd like to see on your post to have it be considered as an addition to our category database!
You can also enable automated category matching on the Post screen. Tap the toggle button for the Category matching option in the Post Settings section. A toggle button that is blue and to the right indicates the feature is enabled. A toggle button that is grey and to the left indicates the feature is disabled.
Note: Post settings indicated on a single thrill post are saved and applied to all future thrill posts until changed.