Overview

Duolingo Duel is a self initiated feature concept developed after a case study prompt I encountered during the Duolingo interview process. I wanted to explore how Duolingo could increase user engagement by introducing a social feature that feels playful, competitive, and easy to integrate into the existing learning experience.

The result was Duel, a 1:1 challenge system where users can invite friends, compete through lesson based prompts, build streaks, and receive celebratory or encouraging feedback based on performance. Alongside the feature flow, I also designed a lightweight A/B testing plan to explore how the feature might affect retention, replayability, and overall engagement.

Key Contributions

• Designed a 1:1 duel feature concept for Duolingo to explore new ways of increasing user engagement through social play.

• Created end to end mobile flows for inviting friends, playing duels, tracking scores, and receiving performance based feedback.

• Introduced streak based scoring and motivational feedback moments to make the experience feel more game like and replayable.

• Considered edge cases such as uneven skill levels, drop off during active duels, and long term replayability.

• Proposed an A/B testing framework to evaluate the feature’s potential impact on retention, stickiness, and repeat engagement.