Duolingo · B2C · language learning app
Let a bandit algorithm pick which upgrade ad each user sees after a lesson
Some wins so far, still improving; no numbers
Workedupsell-expansionexperimentation
What they did
Many creatives promote Super as an ad at the end of a lesson; a bandit optimizes which creative works best for which user.
What happened
'Some wins' and continuing to see wins.
In their words
Sub Club by RevenueCat · How Clarity and Personalization Help Drive Duolingo’s Growth – Anmol Tiwari, Duolingo“And we've had some wins in having a Bandit and trying to optimize which creative will work best for who, and we're continuing to see wins from that.”
Related topics
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More from Duolingo
All 32 Duolingo tactics- Sell a one-time ad-free month at $3, $5 or $10 to test demandUptake far above expectations; led to the subscription
- Tell users on the paywall you'll remind them on day 5 of a 7-day trialWon A/B tests by easing fear of subscription traps
- Change the buy button to say 'Try for $0.00'Beat 'Try for free' on both trial starts and trial-to-paid
- Show one ad only after a lesson ends, and test it against retentionRetention mostly neutral, at most a slight hit, across ad tests
- Count ad complaints per million users and compare them to other complaintsMissing-course complaints were 3x ad complaints; ads launched
- Make paid features free when a test shows they earn littleTook a small revenue hit on purpose to grow free users
More from this episode
- Duolingo: Let trial users pick which day they get the reminder before being chargedTested; added friction but built trust and delayed cancel decisions. No numbers given
- Duolingo: Show what happens on each trial day and exactly how refunds workGuest says clarity beats persuasion for trial starts; no numbers
- Duolingo: When users run out of hearts, offer a free trial so they keep their lesson progressUsers much more likely to start a trial; no numbers
- Duolingo: Ask new users in onboarding if they want to learn with or without adsSignificantly higher uptake; one of the biggest wins of the year
- Duolingo: Cut the free trial from 14 days to 7More conversions overall and experiment results twice as fast
- Duolingo: Offer the same user a free trial three or four times over timeEffective in aggregate across attempts, per guest; no numbers
- Duolingo: Give 3 free days of the paid tier, no card needed, even to current subscribersEffective for free-to-paid and for upgrading subscribers to the top tier, per guest
- Duolingo: Give users one free AI video call from the top tierEffective lever for getting people to try the feature, per guest
- Duolingo: Give the free 3 days as a reward right after a finished lessonFelt more rewarding than on the learning path; no numbers
- Duolingo: When free days end, say 'Your benefits have ended' and show how to rejoin
- Duolingo: Use each user's signals to pick between your own upgrade ads and paid adsGood wins, per guest; no numbers