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12 tactics from Kenneth Schlenker
Why Opal Stopped Chasing Revenue to Build a Billion-User App – Kenneth Schlenker
Watch the full episode“Our paid penetration went from about 20% to 9% and that's scary when you see this chart — but it was the right decision. When you give the product away for free, the people that are using the product become your marketing. We've seen a massive increase in organic growth as a consequence.”
Freemium conversion dropping from 20% to 9% was the right call — free users became Opal's best marketers
Schlenker describes Opal's switch from a hard paywall to freemium: paid conversion cut in half but organic DAU growth exploded. The free tier unlocked students as a second segment — two-thirds of DAUs are now students — which in turn opened a third segment: schools purchasing institutional phone-policy products. Revenue recovered and grew as the larger user base multiplied organic sharing. The counterintuitive principle: for mass-market problems, revenue efficiency and user scale are often in tension, and temporarily sacrificing conversion rate to capture a larger installed base pays back over years.
“If you want the freemium dynamic to really pay out, you need to make sure that the free users are recommending the app — otherwise that doesn't work. If free users are not going to recommend the app and it feels like a trial and it's really capped — you're probably not going to benefit from the organic growth potential of freemium.”
Freemium only works for growth if non-payers would recommend the app — if they wouldn't, give away more
Schlenker offers a practical freemium quality test: ask whether a free user would recommend the app to a friend. If the answer is no, the free tier is not generating the organic word-of-mouth that justifies giving product away. Opal tested different limits on its 'block' feature — users could block 1, 2, 3, or more app categories for free. Three blocks emerged as the sweet spot where free users got genuine value and converted into enthusiastic advocates, while power users naturally wanted unlimited blocks and paid.
“Retention is the ultimate proof of value. If a user comes back you're creating something real. If they don't, nothing else matters. Revenue revenue revenue — but retention really is the only way to have lasting value and the only kind of real moat.”
Retention is the only real moat — if users come back, you're creating something real; if they don't, nothing else matters
Schlenker positions retention not as one metric among many but as the single indicator that validates everything else. Opal reached day-1 to day-7 retention on par with or better than Duolingo, Spotify, and Strava. His argument: it is relatively easy to convince someone to try and pay for a product; retaining them over months and years is the hard part that compounds into a durable business. High early retention is also the prerequisite for the cohort stacking that makes subscription economics work over years.
“The biggest win is streaks. Believe it or not, we have our own way of counting streaks — the streak is represented by this small animated flame — and you can get beautiful opal gemstones when you reach different streak milestones. That's the biggest win in the last year to improve retention and growth.”
Streaks outperformed every other retention feature Opal shipped in the last year
Schlenker names Opal's custom streak implementation as the single highest-impact retention feature of the past year. The streak counts cumulative focus sessions rather than simple daily check-ins, and the visual representation is a bespoke animated flame integrated with the Opal gemstone reward system. Users who hit streak milestones unlock new gemstones. The success is a reminder that well-established gamification mechanics still work when executed with craftsmanship and tied to genuine product behavior.
“Teams create product soul. You can't vibe code a brand. People want to connect with the apps that they use — they want to feel something. A recipe for failure is just to create something that has a function, which AI does really really well. You need more than that to be successful.”
You can't vibe-code a brand — teams create product soul, and soul is what users actually connect with
Schlenker's contrarian take on the 'billion-dollar one-person company' narrative: AI enables fast function creation, but function alone does not create the emotional connection that drives long-term retention and brand loyalty. Opal's brand — the gemstone visual metaphor, the opal-calm-mind etymology, the 'scrolling kills' campaign, the crack-the-gemstone reward interaction — required deliberate human craft. Competitors can copy features; they cannot copy accumulated taste. As AI lowers the cost of building app functions, brand and soul become the differentiator that cannot be commoditized.
“Totally organically — a high school in Los Angeles, Harvard-Westlake, reached out because students got back to them and said many of us are using this app called Opal on our own — no one's telling us to do that — but maybe you should reach out to them.”
Organic school partnerships appeared without sales effort — students emailed their principals about Opal
Schlenker describes how Opal's school business emerged: students using Opal personally recommended it to their schools when districts asked for phone policy solutions. The freemium strategy that brought students in as users was the prerequisite for this B2B2C distribution channel. The pattern mirrors Apple's college library strategy: get the next generation using your product voluntarily, and institutional relationships follow. Opal now charges schools per-student but prices competitively because the brand and word-of-mouth value far exceeds the per-student revenue.
“The way I see competition is I think it's actually a net positive for us. What it does is help more people realize that this problem is real, educate the market, get more people to use apps. There's 5 billion people in the world with a smartphone and probably a few dozen million that have ever used a screen time app.”
Competition is a net positive when you have brand — it educates the market you're trying to win
Schlenker reframes category competition as market-education rather than market-stealing. With only tens of millions of users having ever tried a screen time app out of 5 billion smartphone owners, the primary challenge is category creation, not competitive displacement. Every copycat app that launches runs ads and prompts conversations that expand the category's reach. Opal's brand, retention, and soul mean that users who try inferior alternatives and become dissatisfied will find Opal through word-of-mouth.
“The most loved interaction is the unlocking of that stone — when you get granted a new gemstone because you've passed a new milestone. You get to tap to crack the gemstone and that's the most-talked-about interaction. People really remember this and talk about it and it really helps build the brand.”
The gemstone crack interaction cost weeks of engineering — it became the most-loved moment in the app
Schlenker describes Opal's signature reward interaction: users who hit focus milestones receive an opaque gemstone they can tap to crack open, revealing a new unique gemstone of varying colors and shapes. Schlenker is candid that this was expensive to build and hard to justify on a sprint backlog — there were always 50 more urgent things. But the tap-to-crack gemstone became the interaction users describe to friends, the thing they screenshot, and the moment most associated with Opal as a brand. Unreasonably crafted microinteractions compound into differentiation.
“We found this person who was mentioning Opal in a video on TikTok and thought she was great. We hired her and she's part of the team. The channels are called Olivia Unplugged — she's building educational media for us. We went from zero to 700,000 followers across platforms and millions of views in a few months.”
Hire creators who are already users — they produce authentic content paid agencies cannot replicate
Schlenker describes Opal's creator-first organic growth strategy: rather than running brand accounts, Opal hired a TikTok creator who was already an organic Opal user. She now produces educational content about screen time, focus, sleep, and social skills under her own name with Opal mentioned naturally. The authenticity of creator-led content dramatically outperformed traditional brand social. Opal also licensed an organic video about smartphones that the creator made independently, which reached tens of millions of people and ran as a paid ad.
“If your user wins, you win — that's it. You can add some fancy AI features to the app and you're going to get a lot of early adopters excited about AI right now. But to have lasting value you need to figure out how to make your users win. That's the hardest part.”
If your user wins, you win — AI features should deliver real user value, not just move metrics
Schlenker draws a sharp distinction between AI features that move engagement metrics and AI that actually improves user outcomes. The test: does the AI feature help the user accomplish what they came to the app for — reclaiming focus, building habits, reducing screen overuse? Features that impress in demos but don't serve the core use case will capture early adopters and then churn them. Schlenker's frame for AI is identical to his frame for all product work: ask whether the user is winning after using this feature.
“When you have a great brand you can go from one segment to another to another and build a billion user product. We went from professionals to students to schools — and we see employers, insurers, the family market as logical next steps. That's why it's so important to build the most loved and most important brand in that category.”
A brand can travel across segments — build the most-loved name in your category and new markets open naturally
Schlenker articulates Opal's long-range brand strategy: the same brand that resonated with productivity-focused professionals was elastic enough to capture students, and students' love of the app created a school sales channel organically. He sees expansion into employers, health insurers, and family products as natural brand extensions — each requiring only distribution into a new context, not a new product identity. The enabling condition is that the brand carries emotional weight and mission alignment across segments.
“I think the billion-dollar one-person company is a lie. I think the companies that actually do reach a billion people and billions of valuations — they need more than one person. You need a team, you need a brand, you need retention. AI can improve the value the product gives to users, and then and only then can it really create massive amounts of value.”
Build the team early — the billion-person company myth of solo plus AI is a lie
Schlenker opened his App Growth Annual Tokyo talk with a direct refutation of the popular 'vibe code to $30M solo' narrative. His argument: every massively scaled consumer app — the ones with hundreds of millions of users and billion-dollar valuations — was built by a team with complementary skills, a brand with soul, and retention that compounds over years. AI accelerates product development but cannot substitute for the human decisions that create brand, culture, and trust with users. Opal hit $10M ARR with 11 people; scale beyond that required growing the team further.