I believe that the app has too many categories and planned to have more. However, to be realistic some of these categories will be watched by small amount of people. I think the categories can be decreased and be more general. For example, animation could include fxs and edits. Style could include both style and make-up. And the more specific contents should be in hashtags. The hashtags can be separated in two sections inside of it as: popular and latest so that the hashtags will act as categories but only people who is interested in that content will reach it. I know hashtags such as like4like, rebyte4rebyte will be abused but at the end adding hashtags add more oppurtinty to this app.
Edit: Some popular hashtags can be shown at the bottom of the app, so we can have challenges from hashtags too.