ONEai Health — a clinical monitoring app, from ring basics to seventeen vitals Patients enrol through their healthcare provider and wear an FDA-cleared smart ring. The app had been live about a year when I joined, and its public reviews weren’t about polish — they were about readings that didn’t arrive and a ring that wouldn’t stay connected. I came in as primary Android engineer and built most of what the product does today. The core problem was that health data arrived three different ways — the ring over Bluetooth, Android Health Connect, and the patient typing it in — and each path had grown its own handling. I converged all three onto one per-vital model, so every one of the seventeen vitals renders, charts and uploads identically no matter where its numbers came from. From there: seventeen health-vital surfaces, Health Connect sync, a structured daily diary and an AI chatbot, across roughly seventy-five screens. Then the client brought a new design, and I reimplemented the entire interface against it without touching the business logic underneath — which is the whole argument for keeping the two apart. Live on the App Store and Play Store, now maintained by an internal team