Duolingo · B2C · language learning app
Count ad complaints per million users and compare them to other complaints
Missing-course complaints were 3x ad complaints; ads launched
What they did
What happened
- Stage
- 2016
In their words
Why Your Free Users Are Your Real Growth Engine – Cem Kansu, Duolingo CPO
Cem KansuAnd that's what we did. I mean, in a way, we provided a free service and we kept a lot of the elements free, but we said, "Hey, actually you can buy a streak repair now and you might have to see an ad at the end of your session."
Cem KansuWe got some complaints. The thing that helped us have clarity was, one, retention was fine. Retention was neutral on most of these experiments. And when you looked at our community's complaint volume, if you quantify that, for example, per a million DAUs, how many ad complaints are there or add negative reviews, however you want to count that, versus other topics?
Cem KansuFor example, I realized I did this quantitative analysis in 2016 because we were at this pivotal moment of like, "Do we launch ads or do we not launch ads?" And we looked at, for example, the number of complaints about why we didn't have the finished language on Duolingo was three extra number of people that are complaining about Duolingo having ads.
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New tactics from the week's founder interviews, each linked to where it was said.
More from this episode
- Keep lessons free and sell learners' translations to news sitesSmall revenue; dropped by 2016 (price race and low translation quality)
- Charge $1-3 to fix a broken streakA good share of users paid; showed how much users value their streak
- Show one ad only after a lesson ends, and test it against retentionRetention mostly neutral, at most a slight hit, across ad tests
- Block gambling and sketchy ad types, even if it costs revenueAccepted lost ad revenue for better experience; no numbers
- Sell ads directly to brands and have app characters introduce themUsers like the format; slow to sell because it's custom
- Use the end-of-lesson ad slot to advertise your own paid planGuest says house ads beat programmatic ads; no numbers
- Run 3-6 month holdouts for changes whose effects show up lateNew push lifts can turn negative after about 6 weeks
- Sell a one-time ad-free month at $3, $5 or $10 to test demandUptake far above expectations; led to the subscription
- Launch a plan with no ads, offline use, and 'support our mission'About half of early buyers paid to support the app; started a run rate
- Offer a free trial even though the app is already freeOne of the biggest unlocks; guest had expected it to flop
- 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
- Give subscribers unlimited hearts so mistakes never stop their lessonsBig turning point: raised subscription conversion and retention
- Make paid features free when a test shows they earn littleTook a small revenue hit on purpose to grow free users
- Add new subjects inside the main app instead of launching new appsSeparate apps were 'hard mode'; in-app works better, but many users still don't know
- Offer live human tutors on demand in a higher-priced planFailed: users joined, panicked and left; later replaced by AI video call
Tags: complaints, reviews, decision-making