Clubs is a feature that was once available on Duolingo's mobile application. It was created for the purpose of learners being able to "connect online and stay motivated". This was accomplished by joining a small group that competes for the highest XP score, while also encouraging one another with an emoji-based chat system.
The limit for a club group was fifteen members, and one could make their own club or join someone else's using a six-digit code provided by the club admin. The club admin made decisions regarding who can join, whether they can accept new applications to the club or choosing an avatar for the club.
The arrival of the Leaderboards feature led to the discontinuation of Clubs.