Uploaded February 2026 | Updated September 2026, 6 hours ago

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What does it take to ship a production React Native app that solves a real problem?

At React Universe x Zalando Meetup in Berlin, Tejas Kumar shares how he built a health-focused iOS app that turns Heart Rate Variability (HRV) data into a simple, actionable readiness score.

Instead of another abstract demo, this talk walks through a real TestFlight app used daily by real people.

You’ll learn:

What HRV is and why it matters for stress and burnout
How to access Apple HealthKit data from React Native
Why React Native was chosen over the web
How baseline and trend calculations are implemented in TypeScript
How coefficient of variation (CV) factors into readiness scoring
Why all computation runs on-device
How Expo simplifies builds and App Store deployment
How to evaluate third-party React Native libraries

If you’re building health apps, integrating native APIs, or deciding when to choose React Native over the web, this talk offers a grounded, experience-driven perspective.

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