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11 tactics from Kenneth Schlenker
Lessons from 121 A/B Tests — Kenneth Schlenker, Opal
Watch the full episode“The main metric of success for us has been day-8 return on ad spend. What we try to figure out is not only are people willing to use an app but are they willing to pay for it — and then are we able to acquire customers in a way that makes sense economically with just immediate cash payback.”
Day-8 ROAS as Single Metric Took Opal from Zero to $5M ARR in One Year
Opal scaled from near-zero to $5M ARR in roughly 12 months by anchoring every product and marketing decision to a single metric: day-8 ROAS. The 7-day free trial makes this measurement tight and actionable. When above 100%, they scaled ad spend; when below, they cut back. No forecasting models, no complex attribution — just one number everyone understood.
“From the very first week on the App Store until today we've released one app version every single week on Monday. By Thursday you're like let's get something in because I want to see the number change next week.”
Weekly Shipping Cadence Creates the Iteration Rhythm That Makes 121 Tests Possible
Opal shipped a new app version every Monday without exception, from launch through $5M ARR and beyond. This cadence created a natural experiment loop: change something Monday, measure the effect by the following Tuesday when day-8 cohort data lands. Without this discipline, 121 A/B tests in the same period would have been impossible.
“You're looking for the peak motivation moment — if you need a few screens to build motivation and build intent, then display the paywall. After we make that projection we tell you the good news is we can save up to three, four, five years of your life together — that's the moment where there's high motivation.”
Show the Paywall at Peak Motivation — After the 22-Years-of-Screen-Time Report
Opal tested dozens of paywall placements and converged on showing it immediately after the onboarding lifetime screen time report — a moment of peak anxiety and motivation. This sequence lifted trial start rates from 7% to 17% of all downloads. The principle: the paywall must arrive at the precise moment when the user most wants to change. Finding that moment is the design challenge.
“If you onboard people to committing to something where they don't need to remember later to do it — an automatic action — what happens is you onboard, you exit out of the app, and then the next day you don't need to remember. It'll just start to block the app and you'll remember: oh, I committed to this, now I'm in.”
Auto-Scheduling a Session in Onboarding Eliminates the Remember-to-Use-It Failure Mode
Opal's biggest onboarding win was creating an automatic Mon-Fri 9-5 blocking session for the apps the user named as distractions. The user doesn't have to return to activate it — it just fires the next morning. This sidesteps the most common reason productivity apps churn in week one: the user forgets to engage. Default-on beats opt-in when the product goal is behavior change.
“Whenever we tried to give people more choice in the onboarding it failed. Users have a limited fatigue budget — they're only going to make so many choices. You need to make sure you're spending that mental energy on exactly the things that matter.”
Too Much Choice in Onboarding Is a Consistent Loser — Default Beats Customization
Opal ran multiple tests offering users flexibility to customize their blocking schedule during onboarding. Every variant with more choice performed worse than the opinionated default. Onboarding is not the place to exercise preference — it's the place to get the user to their first win as fast as possible. Let them edit later; commit them to something automatic first.
“Someone made this video before we ever reached out to them. It wasn't about Opal — it was just about the space. They wrote back and said actually I use Opal and I love it. We said can we use this video as an ad and they said yeah sure.”
Mission-Aligned Creators Who Already Use the Product Outperform Agency Creative
Opal's best-performing ad was filmed by a creator who had never been paid by the company. It didn't even show the product — it captured the mission of reclaiming time from your phone. Opal repurposed it with minor tweaks and it dominated their campaigns. Finding creators who already use the app and care about the problem proved more reliable than agency or contractor creative.
“When people cancel their trial we re-engage them with an offer and that works quite well. It's really interesting that they're non-committed enough to be like no I'm not paying for this — but then you present them with a deal and they take it.”
Re-Engage Trial Cancellers With a Discount Offer — It Works Even When Intent Seemed Low
Opal sends a 50% discount offer to users who cancel their free trial via push notification and in-app modal. Despite the canceller's apparent low intent, this re-engagement converts at a meaningful rate. Trial cancellers are still in-app, still context-aware, and a discount reframes the commitment. This was one of the few post-onboarding re-engagement experiments that succeeded out of many failures.
“Changing the opacity of the X button on the paywall to 80% increases Revenue 20%. You're like okay why do I even try? I've built a long buildout feature that has very little impact even though it's beautiful.”
Test Big Swings First — X-Button Opacity Change Beat Months of Feature Work
Opal ran A/B tests on major features and minor UI details alike. The most jarring result: making the dismiss X button slightly less opaque on the paywall lifted revenue by 20%, while weeks-long feature builds moved nothing. This is an argument to ruthlessly estimate expected uplift before starting any build, and to run the quick-win tests first before long investments.
“We figured out how to get people to pay — a smaller number — but now we're looking at how do we expand this to many many more people including people using it for free. Our paid penetration is 17% versus Duolingo's 8% — which means we can probably have a lot more people using the product for free.”
Prove Willingness to Pay First, Then Build the Freemium Funnel Around It
Opal deliberately reversed the typical freemium trajectory: instead of building free usage first and monetizing later, they proved payment willingness before opening the funnel wider. With 17% paid penetration and a clear conversion baseline, the move to freemium is a deliberate growth expansion from a profitable position — not a leap of faith.
“We ask people in onboarding where they came from and we found that to be actually the most reliable way of doing attribution. At the end of the day just asking people where they heard about us — if they say Facebook it's one thing, word of mouth something else.”
Simple Where-Did-You-Hear-About-Us Survey Beats Fancy Attribution Software
Opal tried multiple attribution platforms but found a direct onboarding survey question the most actionable signal. At seven people there's no bandwidth to act on granular campaign-level data anyway — knowing that most conversions come from Facebook vs. word of mouth is enough to allocate resources. The dumbest measurement is often the most reliable and the most actionable.
“One very small change: we made the referral program look better and added a tiered reward system — invite five people get the free year, invite 20 get a lifetime sub, a special prize at 50. This led to 80% improvement in how many people sent the referral to at least one person.”
Tiered Referral Rewards UI Delivered 80% More People Sending at Least One Invite
Opal improved its referral program with a tiered reward structure and visualized progress in a well-designed UI. The result was an 80% improvement in single-invite sends. No new incentive budget was required — the change was purely structural, transforming an opaque invite screen into a gamified goal with clear progression milestones that motivated users to take that first share action.