Papaya — iOS to Android port, Clean Architecture from scratch

The Engagement

Jenevive Health’s Papaya is a healthcare-tracking app — iOS-first, with a complex treatment-details flow and a body-map interaction users tap to mark areas of interest. The Android client didn’t exist. I joined as Android Architect / Lead Engineer in June 2022.

There was almost no written spec. The iOS app was the reference.

What Shipped

• Built from scratch in Clean Architecture. Compose UI, MVVM presentation, Hilt DI, Room for local state. The architectural freedom was the gift of the engagement — clean layering paid off across every later feature.
• Custom calendar. The iOS calendar was bespoke — date picker, treatment markers, multi-select range — and there was no off-the-shelf Compose equivalent. Built it from primitives.
• Treatment-details flow, 20 mappers deep. The hardest screen. A complex nested data structure had to render fast and stay editable; the presentation layer ended up with ~20 mappers between the domain model and the UI state so the screen could stay smooth without locking the data model.
• Body-map via C++ NDK. A native body-anatomy library (third-party C++) drove the body-map selection screen. Second time integrating an NDK library; the library exposed enums where sealed classes would have been cleaner, which I noted but worked around rather than rewrote.

Result

Android shipped at parity with iOS in 6 months. The Clean Architecture pattern carried forward as Jenevive’s Android standard.

Public listing: com.jenevive.papaya on Google Play (developer: Jenevive Health).

Stack

Android · Kotlin · Jetpack Compose · C++ · Clean Architecture · MVVM · Hilt · Room · SDK + NDK · GitHub Actions · Firebase Analytics / Crashlytics / Releases