Case Studies

Results that speak for themselves.

Detailed breakdowns of past engagements, the problems, the approach, and the measurable outcomes. Most engagements arrived through the engineer retainer or Android development work; the cases below show what shipped.

HBO GO Android — Architecture Modernisation & Performance

Hardened the UI layer of HBO GO's Android app for 10M+ users, cutting recurring UI defects from roughly 50% of weekly bug reports to about 5% and saving an estimated €100k/yr in engineering time, then modernised the architecture (Kotlin migration, MVVM + Hilt) and drove a 40% crash reduction.

AndroidKotlinMVVMPerformanceArchitecture

50% → 5%

Recurring UI issues

€100k/yr

Engineering time saved

Yahoo Daily Fantasy — Android Architecture Refactor

Contributed to the Yahoo Daily Fantasy Sports Android app as an engineer focused on architectural improvements — migrating legacy patterns to MVVM to make the codebase easier to extend and test.

AndroidKotlinMVVMArchitecture

Preglife — #1 lifestyle app in client's country, rebuilt from scratch

Sole lead Android engineer on Preglife's rebuild. The app went on to become #1 in lifestyle on Google Play in the client's home country; it now sits at 1M+ installs and 5.0★ from 38K reviews on Play Store.

AndroidConsumer healthPregnancy trackerMaterial DesignLead engineer

Lifestyle app in client's home country

1M+

Lifetime installs on Google Play

AR Art Projector — AR pipeline rebuild, OpenGL to ARCore

Replaced the OpenGL-based camera + AR pipeline with ARCore on a ChatGPT-built codebase that had no architecture. Shipped through beta and into production; Da Vinci Eye relaunched on Android in Feb 2026 at 4.64★ from 1.2K reviews and 190K+ installs.

AndroidARARCoreCamera2KotlinJetpack Compose

4.64★

Rating after rebuild (1.2K reviews)

190K+

Installs since 2026 relaunch

Papaya — iOS to Android port, Clean Architecture from scratch

Ported Papaya from iOS to Android by rebuilding the Android client from scratch against the iOS reference, with almost no spec. Clean Architecture; custom calendar; a 20-mapper treatment-details flow; a body-map screen driven by a C++ NDK library.

AndroidCross-platform portJetpack ComposeClean ArchitectureNDKHealthcare

6 months

iOS to Android port, Clean Architecture from scratch

20 mappers

Treatment-details data layer

FYX Driver & Mechanic — Two-app marketplace, sole senior Android engineer

Solo senior Android engineer on FocusTapps' two-sided roadside marketplace — driver app, mechanic app, plus an Ionic cross-platform companion. Two-year engagement (longest single contract at the time): real-time push, location and maps, LibGDX 3D models, image capture and upload.

AndroidMarketplaceMulti-appFirebaseGoogle MapsLibGDXIonic

2 years

Longest single engagement at the time

3 apps

2 native Android + 1 Ionic cross-platform

Journey Rewards — Stepping In Mid-Flight

Led a 7-engineer mobile team at Journey Rewards as Head of Mobile, moving development from outsourced to in-house and accelerating delivery with Claude PR reviews and build automation across iOS, Android, and KMM.

AndroidiOSKMMKotlinJetpack ComposeLeadershipCross-Platform

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