Choosing React Native and Expo meant that we were able to build an app in record time. Speed was critical during the early days of the pandemic. And since 99+% of our codebase was platform agnostic, we onboarded two additional web developers in 24 hours, something we could never have done using Swift and Kotlin.

The timeline we were able to achieve with Expo is what really astounded us: 36 hours after the first line of code, we were live on both the App Store and Google Play Store. The following few days, if there was a bug, we were able to identify and fix it in seconds thanks to Expo's Over the Air Updates. In the rapidly changing environment of the pandemic, it’s essential for us to quickly release to stay ahead of the curve and have the most meaningful data available for our data scientists. Over-the-Air Updates enable us to deliver new features instantly to our users, and send out bug fixes quicker than we could've ever imagined.

As you can tell, speed is our modus operandi. Previously, we were writing separate native Swift and Kotlin apps. This was a problem, since as a small startup, we were trying to iterate fast and find product-market fit. Releasing natively on both platforms required having two engineering teams, and because of the slower release speed, we weren't learning the way we wanted to. Once we made the switch to React Native & Expo, this problem disappeared, since the work was basically cut in half. For example- one feature we love from Expo is everything around notifications. All the complexity is abstracted away in favor of one simple API, so that end-to-end we never have to think about platform-specifics.

We’ve not yet reached any major limitation for the features we’ve wanted to develop. So far, our experience is that React Native works well, even when installed on 2+ million devices of all shapes and sizes, and we're excited to continue growing with Expo.

Julien Lavigne du Cadet, VP of Engineering

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