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Is Your App Guesswork? A/B Testing the Truth in React Native

Sep 9, 2025· 22 min· 1.4K views·Watch on YouTube

Speaker

Violina Popova of ClipMyHorse.TV talks about using A/B tests to improve onboarding and product decisions in a React Native app at RUC 2025, presented by Callstack.

Removing the signup barrier

Popova describes how ClipMyHorse.TV offered a free trial behind a welcome and signup screen, but many users cancelled when the trial ended. In tests in France and Sweden, users who could explore streams without logging in or starting a trial led to 25% more paid subscribers. The result prompted the team to focus on letting users experience the app’s value sooner.

Testing design assumptions

Popova shares a filter button test where variant B outperformed variant A by more than 100%, despite the UX team betting on A. The team refined the design using interaction data and worked across design, product, and engineering to question assumptions. She connects this approach to developers taking a broader role in product and user experience decisions.

Planning and running experiments

A/B testing compares versions that differ in one change, shown randomly to users, to measure outcomes such as clicks, conversions, or retention. Popova recommends a clear hypothesis, minimal variants, defined success metrics, and enough users and time for reliable results. ClipMyHorse.TV uses Firebase Remote Config to manage variants, with gradual rollouts and kill switches to control mobile releases.

Measuring results and avoiding pitfalls

Popova advises choosing a primary success metric and guardrails, such as checking that more video starts do not coincide with lower session time or higher crash rates. Common mistakes include testing too much at once, starting without a hypothesis, stopping before results are significant, and overlooking users on older app versions. Teams should also remove retired experiment code.

Building a learning culture

At ClipMyHorse.TV, developers and product managers share experiment ideas and results, including failures, and track tests in a backlog. Popova says ongoing experimentation helped raise the app’s ratings from 2.5 to 4.5 stars on Android and 4.7 on iOS. She recommends starting with small, purposeful tests and using results to guide the next iteration.

Takeaways

  • Let users reach the product’s value before asking them to sign up; test whether that improves paid conversion.
  • Write a measurable hypothesis and change one thing at a time so results are easier to interpret.
  • Define a primary metric and guardrails before a test begins, then allow enough time and traffic for reliable results.
  • Use gradual rollouts and kill switches to manage experiments in mobile apps.
  • Track and share experiment outcomes, and remove retired test code from the app.

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