Mobills increases subscription conversions by 15% with Firebase A/B Testing

In 2013, two tech students from Brazil founded Mobills, an easy-to-use personal finance app that helps users control their expenses. With more than 8 million downloads, Mobills helps users manage over 1.5 million credit cards and tracks purchases from more than 300 million companies and counting.

What they did

When the team at Mobills wanted to increase their subscription and registration conversion rates, they looked for ways to improve their app. They identified two areas of opportunity: a long, single-page registration form and a potentially unclear call to action (CTA).

To see if spreading out the registration form over multiple screens would increase conversions, they built a new version to test against the original. They also tested the original subscription CTA — “Assinar agora,” or “Subscribe now” — against a new version, “Seja premium” (“Become premium”). Using Firebase A/B Testing and Remote Config, the Mobills team was able to roll out the experiment to a small set of users without republishing their app.


The experiments were a success. The new, multi-step registration form led to a 2% higher conversion rate than the original, while the new CTA increased subscription conversions by a whopping 15%.

After sharing the results with the rest of the company, Mobills now empowers each staff member to run their own A/B tests. Using Firebase, Mobills says they can find solutions faster and keep improving their app’s performance.

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All app and game developers can use Firebase A/B Testing to improve their app’s business results. Get started today!