Zero-to-App in 14 Weeks for a B2C Health Platform
React Native app launched on iOS and Android simultaneously, hitting 12,000 downloads in the first month with a 4.8-star rating — and a Day-30 retention rate 3× the industry average.
14 wks
Zero to App Store
12k
Month-1 downloads
4.8★
App Store rating
68%
Day-30 retention
A health app that people actually use.
The founding team — two physicians and a product designer — had a clear vision: a consumer health app that bridged the gap between clinical care and daily wellness habits. They had $1.8M in seed funding, a 14-week window before a major health conference, and no engineering team.
The stakes were high. Health apps have a notoriously brutal retention curve — most lose 80% of users within 30 days. The founders knew that building fast wasn't enough; they needed to build something people would actually come back to. That required getting the product fundamentals right before writing a single line of code.
The process
Product Definition & UX Research
We ran a two-week product sprint with the founding team — 18 user interviews with target patients, competitive teardowns of 12 health apps, and a Jobs-to-be-Done workshop that surfaced the core insight: users didn't want another health tracker, they wanted a "health coach in their pocket." This reframed the entire product direction.
- 18 user interview transcripts
- JTBD framework
- Competitive analysis
- Revised product brief
Design System & Prototype
We built a complete design system in Figma — 140 components, 6 screen templates, and a motion language guide. The prototype was tested with 30 users before a single line of code was written. We iterated through 3 rounds of usability testing, reducing task completion time for the core flow from 4.2 minutes to 47 seconds.
- 140-component design system
- Interactive Figma prototype
- 3 rounds of usability testing
- Motion language guide
React Native Build
Built in React Native with Expo for maximum code sharing between iOS and Android. The app featured real-time health data sync via HealthKit and Google Fit, an AI-powered symptom checker, push notification system with personalized nudges, and an in-app telehealth booking flow. Performance was a first-class concern — 60fps animations throughout.
- React Native app (iOS + Android)
- HealthKit & Google Fit sync
- AI symptom checker
- Telehealth booking flow
App Store Launch & Growth Instrumentation
App Store Optimization was built into the process from day one — keyword research, screenshot A/B testing, and a launch PR strategy that landed coverage in 3 health tech publications. We also instrumented the full analytics stack: Mixpanel for product analytics, Amplitude for retention cohorts, and a custom health outcomes dashboard for the clinical team.
- ASO strategy & execution
- Launch PR (3 publications)
- Mixpanel + Amplitude setup
- Clinical outcomes dashboard
Results at a glance
14 wks
Zero to App Store
iOS & Android simultaneously
12k
Month-1 downloads
organic, no paid acquisition
4.8★
App Store rating
across 1,400+ reviews
68%
Day-30 retention
vs. 22% industry average
Stack used
Mobile
- React Native
- Expo
- TypeScript
- Reanimated 3
Backend
- Node.js
- GraphQL
- PostgreSQL
- Redis
Health APIs
- HealthKit
- Google Fit
- FHIR R4
- Epic MyChart
Analytics
- Mixpanel
- Amplitude
- Segment
- Firebase
From idea to App Store.
We build React Native apps that users actually keep. From product strategy through launch and growth instrumentation — we've done it before.