• Duolingo's Wednesday earnings call started with an AI chatbot demonstration.
• The chatbot, Lily, summarized the company's performance this quarter.
• Despite revenue growth, Duolingo missed paid user targets, and its stock fell 5% in late trading.

Duolingo kicked off its latest investor call on Wednesday with a new voice: Lily, an artificial intelligence-driven chatbot based on a longtime app character.

The purple-haired chatbot, which sounded like a bored, sarcastic teenager, replaced CEO Luis von Ahn at the beginning of the video call. Von Ahn later took questions from analysts.

"Over time, she's going to do more and more of my job, and I can just retire," the CEO said.

Speaking in English for less than two minutes, the chatbot summarized the quarter's performance, including key metrics like daily active users, which grew 54% year over year to 37.2 million. Lily attributed Duolingo's strong growth to social media marketing and investments in generative AI.

"Our new Duolingo Max feature video call lets learners chat with me," the chatbot said. "Don't worry, I won't judge — much. Maybe just an eye roll here and there."

Lily's earnings call appearance is another instance of Duolingo's marketing strategy that positions the brand as a person, not as a business.

The chatbot highlighted the company's efforts to double down on AI. Duolingo uses OpenAI's GPT-4 for two-way interactions and, earlier this year, cut 10% of its contractors as AI, not people, creates lessons.

Several analysts attending the call acknowledged Lily's appearance. Piper Sandler's Arvind Ramnani said on the call that it was "probably one of the most enjoyable earnings calls that I had in several quarters."

While Lily was largely a gimmick for the earnings call, the impact of AI has been a persistent theme in earnings this year. Key discussions this quarter include AI's creative use and infrastructure spending for tech giants like Meta and Microsoft.

Duolingo reported $192.6 million in revenue, which beat analyst expectations of $189.2 million and was a 40% year-on-year improvement. Duolingo also raised full-year 2024 revenue guidance from up to $738 million to as much as $744 million.

However, the company missed Wall Street's expectations on one key metric. It reported 8.6 million paid subscribers, while analysts predicted 8.66 million. Duolingo fell nearly 5% in after-hours trading following the earnings report.

Its stock is up over 40% year-to-date, following six straight profitable quarters.

The app, a hit with Gen Z, is most famous for its gamified approach to language learning, where users try to maintain a daily usage streak. In September, the company launched a feature where users can video call Lily and practice speaking with the bot, part of its most expensive pricing tier.

The company didn't immediately respond to a request for comment for this story, sent outside business hours.