Available to hire
I’m Phillip Bunnell, a Senior Mobile Software Engineer with over 10 years delivering high-performance Android and iOS apps for enterprise, SaaS, and consumer platforms. I excel in Kotlin, Java, Swift, and Flutter, and I’m comfortable end-to-end from API design to CI/CD, with a focus on secure, offline-first experiences.
I’ve mentored engineers and collaborated across product, design, backend, DevOps, and security teams to ship reliable mobile experiences. I thrive on building scalable mobile architectures, improving performance, and delivering measurable business value through secure payments, analytics dashboards, and automated workflows.
Language
English
Fluent
Work Experience
Senior Android Engineer at Tryon Creek Software
September 1, 2022 - June 1, 2026Developed secure internal Android applications using Kotlin, Jetpack libraries, Jetpack Compose, and MVVM for enterprise engineering and operations teams. Implemented real-time sync with Google Cloud Pub/Sub, Firestore triggers, and Cloud Functions to support collaborative updates, instant notifications, and automated workflows. Designed mobile API clients with retry logic, offline queueing, smart caching (Room), and WorkManager to improve reliability in low-connectivity environments. Implemented OAuth 2.0 SSO with Azure Active Directory and Spring Security for enterprise authentication across mobile and backend systems. Built accessible and responsive user interfaces supporting TalkBack and reusable components for multiple internal personas. Created Jenkins, Gradle, and Firebase App Distribution pipelines for automated builds, QA testing, canary releases, and internal app distribution. Defined mobile security practices for internal APIs, including token lifecycle handling, role-based
iOS Developer at Microsoft
June 1, 2019 - August 1, 2022Architected the full development lifecycle of cross-platform mobile applications using Flutter, Dart, Kotlin, Java, Swift, and SwiftUI for enterprise SaaS solutions. Designed complex in-app features including URL shortening, QR codes, branded links, and analytics dashboards with responsive mobile visualizations. Integrated Stripe and Braintree payments with subscription-state handling, secure tokenization, and webhook coordination, achieving 50% faster payment flows. Built offline-first functionality to ensure uninterrupted app usage in low-connectivity environments, including caching, deferred asset loading, and background synchronization. Reduced crash rates by over 40% through proactive monitoring, logging, regression testing, and real-time crash reporting using Sentry and Firebase Crashlytics. Mentored junior developers, conducted code reviews, and enforced clean architecture principles, increasing team productivity and reducing technical debt. Partnered with product, design, backe
Mobile Application Developer at SpotSource
March 1, 2017 - June 1, 2019Developed and maintained enterprise Android applications using Kotlin and Jetpack libraries, implementing Flutter for cross-platform projects. Implemented secure authentication workflows, role-based permissions, and encrypted local storage using OAuth 2.0 SSO. Built real-time synchronization features with Google Cloud Pub/Sub, Firestore triggers, and Cloud Functions. Designed resilient mobile API clients with offline queueing, smart caching, retry logic, Room persistence, and WorkManager for guaranteed data delivery in low-connectivity scenarios. Created Jenkins, Gradle, and Firebase App Distribution pipelines for automated builds, UI tests, canary releases, and internal app distribution. Collaborated with UX designers to create accessible, responsive interfaces supporting TalkBack and reusable components.
Android Developer at Datatrak Powered by Fountayn
January 1, 2015 - February 1, 2017Developed Android applications with offline-first architecture, secure login, real-time updates, and dashboards. Translated product requirements into functional and maintainable mobile code with reusable UI components. Optimized app performance and stability, reducing crash rates and improving user satisfaction. Implemented real-time sync with Google Cloud Pub/Sub, Firestore triggers, and Cloud Functions to support collaborative updates, instant notifications, and automated workflows. Designed mobile API clients with retry logic, offline queueing, smart caching, Room, and WorkManager to improve reliability in low-connectivity environments. Implemented OAuth 2.0 SSO with Azure Active Directory and Spring Security for enterprise authentication across mobile and backend systems. Built accessible and responsive user interfaces supporting TalkBack, clear navigation patterns, and reusable components for multiple internal user personas. Created Jenkins, Gradle, and Firebase App Distribution p
Education
Bachelor's Degree in Computer Science at The University of Texas at Austin
April 1, 2010 - December 1, 2014Qualifications
Industry Experience
Software & Internet, Professional Services
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