Jake from Verbling here. Beginner/intermediate/advanced refer to the different levels of conversation topics available to users. You can click through all of them while you're in a conversation, so you're never "stuck" in any of the categories. Specifically, at the beginner level, you're exposed to mostly the present tense and beginner's vocab. At the advanced level, you'll see some conditional tense and more advanced vocabulary, for example re. politics, culture, technology.

Re. ratings: We simply ask you, "How was your conversation?" Based on whether you superlike/like/dislike, we can pair you up with that same native speaker more often, at the same rate, or never again.

Hope this helps!