Independent Senior Mobile Engineer

Modernise your Android app.Adopt Kotlin Multiplatform without a rewrite.

I'm David Cruz Anaya. I help mobile product teams improve ageing Android codebases, introduce shared Android and iOS architecture, and build performance-critical native modules when Rust is the right tool.

12+ years shipping production mobile products used by millions across Sky, MGM, WWE and BritBox.

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Two ways to work with me

Pick your route

For companies

Ship senior mobile work

Android app modernisation, Kotlin Multiplatform adoption, native Rust modules when they earn their place, and embedded senior delivery.

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For developers

Grow as a developer

One-to-one mentoring in Android and Kotlin, Kotlin Multiplatform guidance, code and architecture reviews, and career support.

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What I do for companies

Senior mobile engineering, where it counts

Android app modernisation

Bring an ageing Android codebase up to a modern standard: Kotlin, Jetpack Compose, a modular architecture, and the test and CI/CD groundwork that makes future features cheaper.

Kotlin Multiplatform adoption

Share business logic across Android and iOS without a rewrite. Incremental migration, proven on one feature first, with your team able to keep going.

Scalable mobile architecture

Architecture and technical leadership for Android and iOS: clear module boundaries, testability, and standards that hold as the product and team grow.

Native Rust modules

Advanced

An advanced specialisation, used only when it is justified: performance-critical modules in Rust (audio, cryptography, parsing) exposed cleanly to Android and iOS.

See how each engagement works

Selected mobile work

Shipped to millions

A low-latency Kotlin Multiplatform audio SDK, streaming apps for Sky, BritBox and NOW, and a regulated sportsbook and casino. Each is written up as a real case.

RustWeb FrameworkOpen Source
Churust
Churust (churro + Rust) is an open-source web framework that brings Ktor's developer experience to Rust: a server builder, routing DSL, install(plugin), typed extractors, and secure defaults on tokio, hyper, and rustls. Published on crates.io with lockstep multi-crate releases, a full test matrix, and a public user guide.
Live GitHub
Kotlin MultiplatformAudioKMP
Klarinet
Klarinet is an open-source Kotlin Multiplatform audio SDK: one idiomatic Kotlin API for low-latency playback, recording, file I/O, and real-time effects across Android and Apple platforms. Under the hood it delegates to the best native backend on each platform: Google Oboe (AAudio / OpenSL ES) on Android, AVAudioEngine on Apple. A shared C++ DSP core powers 16 hot-swappable, lock-free effects. Published on Maven Central.
Live GitHub
AndroidiOSDRM
Sky Go
Sky's flagship streaming app for live TV and on-demand content, with offline downloads, multi-device playback, and DRM-protected adaptive streaming across the UK and Europe.
Live
AndroidJavaDagger
BetMGM
Sports betting and online casino mobile app for US regulated markets, with live in-play wagering, a Same Game Parlay builder, casino and live-dealer games, and geolocation-gated, state-by-state compliance.
Live
AndroidStreamingNative
BritBox
BBC and ITV's subscription streaming app for British TV: boxsets, exclusive premieres, originals, and live channels, with offline downloads and casting on Android.
Live
KMPCMPKotlin
KMP SaaS Kit | Production-Ready Kotlin Multiplatform Starter for iOS & Android
Every mobile SaaS app needs the same foundation: authentication, subscriptions, onboarding, settings, theming. You've built it before. It took weeks. Then you did it again. KMP SaaS Kit provides a solid foundation: production-ready, compatible with both platforms, and built on a single codebase. Skip 6-8 weeks of boilerplate and ship your app this week.
Live
AndroidiOSStreaming
NOW
Sky's contract-free streaming app for live TV, on-demand boxsets, movies, and sports across 60+ devices, with no fixed contract, downloads, and 4K HDR with Dolby Atmos.
Live

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TRUSTED BY

Companies I've Worked With

TESTIMONIALS

What Clients and Colleagues Say

Selected feedback from Android, mobile and engineering-leadership colleagues I've worked with.

Sourced from LinkedIn recommendations

“I worked closely with David during our time at Sky. I initially heard about him from others as “this great coder who had left our team”, but later I had the chance to personally get to know him and to discover many great components and features he had designed. His code was easy to read and, to this day, serves as the foundation for a shared video-streaming library at Sky. David’s passion for coding makes him one of the most hard-working people I have had the chance to meet. He is constantly learning new things and sharing his knowledge with others. He is also comfortable challenging the status quo to improve both products and processes. I have seen this a few times while at Sky when he proposed different technologies stack that led to better products. I would trust David with any project that needs to be brought to life and built for maintainability and long-term success.”

Raul Podar

Senior Android Engineer @ Sky

“Working with David as my manager was a positive experience, and I recommend him for his solid technical skills. He adeptly combines strategic vision with hands-on expertise, simplifying complex projects. His guidance created a collaborative and innovative team environment, and his dedication to our success was evident in every project. David is not only a seasoned professional but also a trusted mentor with a friendly approach. I would eagerly work with him again, confident that any team would benefit from his technical expertise.”

Junaid Younus

iOS Contractor @ JustEat

“Had the pleasure of working in a software delivery team under David's guidance as Scrum Master. I learnt much to develop my own mentality and approaches to software development. Both smart and professional, as well as a valued mentor of mine, I can easily recommend both his character and technical skillset.”

Patrick Ellis

Retired @ Sky

“During my years as a developer, I have worked with several people. However, only a handful are as talented as David. He is simply outstanding and doesn't matter what's the task, he will get it done in no time. It was a pleasure to work with him in the Sky Go team!”

Ian Nagot

Principal Engineer @ Sky

“David and I worked together on the Android Sky Go project, where I found him an absolute joy to work with. He tackled every request made of him with zeal, and nothing was too much trouble. He excelled at detailed investigations on a complex codebase, constantly strove to improve his skills, and gladly shared his knowledge and his time with the rest of the team. I would never hesitate to recommend him for any work he wished to set his mind to.”

Mark Rymer

Lead Software Engineer @ Sky

“I had the pleasure of working with David on a key company project for a large international client. As Android team lead, David's engagement and eagerness to convey ideas and feedback were pivotal in not only the success of the final product, but also in the learning process of the junior developers he mentored. These are qualities I value in strong technical team leaders. David has my full recommendation.”

Eduardo Calçada

Engineering Program Manager @ Apple

“Great person to work with, as a colleague and mentor. David has a strong understanding of the Android ecosystem, not only of the development side but also the tools and programming paradigms that surround it.”

Jose Terrones Arroyo

Sabbatical @ Freelance

Have a mobile problem worth solving?

Tell me about your app and where it is stuck. If I am the right fit, we will scope it. If I am not, I will say so.

Discuss your mobile project

Modernise your Android app.Adopt Kotlin Multiplatform without a rewrite.

Pick your route

Ship senior mobile work

Grow as a developer

Senior mobile engineering, where it counts

Android app modernisation

Kotlin Multiplatform adoption

Scalable mobile architecture

Native Rust modules

Shipped to millions

Churust

Klarinet

Sky Go

BetMGM

BritBox

KMP SaaS Kit | Production-Ready Kotlin Multiplatform Starter for iOS & Android

NOW

Companies I've Worked With

What Clients and Colleagues Say

Have a mobile problem worth solving?

Mentoring

Blog

Book

Speaking