We use Clojure for large data processing where it shines. It's also good at doing concurrency with it's solid concurrency tools and immutability by default. So a lot of people use it for financial data, fraud, and big data stuff. I think it's less common, but using Re-frame both in a front-end web app and also in a React Native mobile app was a charm. Some of the environments were a little hard to get going but were a dream to poke around and add lots of features quick. For example, the whole Urban Dictionary native app for iOS and Android are in Clojure as well as most of the site.