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I am a Senior Mobile Engineer and Tech Lead with over 11 years of experience in designing, developing, and scaling high-performance mobile applications for iOS and Android. I have a strong background in healthcare, telemedicine, e-commerce, and IoT domains, focusing on building secure, scalable systems using modern technologies like Swift, Kotlin, React Native, and more. I take pride in creating pixel-perfect UI/UX aligned with best platform practices while optimizing performance and security. My experience extends from native mobile development to cross-platform apps, continuous integration and delivery, accessibility, and real-time data synchronization. I enjoy bridging mobile, backend, and DevOps layers to deliver reliable production-ready apps. Working collaboratively with cross-functional teams, I aim to provide seamless user experiences and innovative solutions tailored to the needs of healthcare and e-commerce industries.…I am a Senior Mobile Engineer and Tech Lead with over 11 years of experience in designing, developing, and scaling high-performance mobile applications for iOS and Android. I have a strong background in healthcare, telemedicine, e-commerce, and IoT domains, focusing on building secure, scalable systems using modern technologies like Swift, Kotlin, React Native, and more. I take pride in creating pixel-perfect UI/UX aligned with best platform practices while optimizing performance and security. My experience extends from native mobile development to cross-platform apps, continuous integration and delivery, accessibility, and real-time data synchronization. I enjoy bridging mobile, backend, and DevOps layers to deliver reliable production-ready apps. Working collaboratively with cross-functional teams, I aim to provide seamless user experiences and innovative solutions tailored to the needs of healthcare and e-commerce industries.

Dwayne K Mansfield

App Developer, Developer, Full Stack Developer, +2

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I am a Senior Mobile Engineer and Tech Lead with over 11 years of experience in designing, developing, and scaling high-performance mobile applications for iOS and Android. I have a strong background in healthcare, telemedicine, e-commerce, and IoT domains, focusing on building secure, scalable systems using modern technologies like Swift, Kotlin, React Native, and more. I take pride in creating pixel-perfect UI/UX aligned with best platform practices while optimizing performance and security. My experience extends from native mobile development to cross-platform apps, continuous integration and delivery, accessibility, and real-time data synchronization. I enjoy bridging mobile, backend, and DevOps layers to deliver reliable production-ready apps. Working collaboratively with cross-functional teams, I aim to provide seamless user experiences and innovative solutions tailored to the needs of healthcare and e-commerce industries.…I am a Senior Mobile Engineer and Tech Lead with over 11 years of experience in designing, developing, and scaling high-performance mobile applications for iOS and Android. I have a strong background in healthcare, telemedicine, e-commerce, and IoT domains, focusing on building secure, scalable systems using modern technologies like Swift, Kotlin, React Native, and more. I take pride in creating pixel-perfect UI/UX aligned with best platform practices while optimizing performance and security. My experience extends from native mobile development to cross-platform apps, continuous integration and delivery, accessibility, and real-time data synchronization. I enjoy bridging mobile, backend, and DevOps layers to deliver reliable production-ready apps. Working collaboratively with cross-functional teams, I aim to provide seamless user experiences and innovative solutions tailored to the needs of healthcare and e-commerce industries.

Available to hire

I am a Senior Mobile Engineer and Tech Lead with over 11 years of experience in designing, developing, and scaling high-performance mobile applications for iOS and Android. I have a strong background in healthcare, telemedicine, e-commerce, and IoT domains, focusing on building secure, scalable systems using modern technologies like Swift, Kotlin, React Native, and more. I take pride in creating pixel-perfect UI/UX aligned with best platform practices while optimizing performance and security.

My experience extends from native mobile development to cross-platform apps, continuous integration and delivery, accessibility, and real-time data synchronization. I enjoy bridging mobile, backend, and DevOps layers to deliver reliable production-ready apps. Working collaboratively with cross-functional teams, I aim to provide seamless user experiences and innovative solutions tailored to the needs of healthcare and e-commerce industries.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Work Experience

Senior Mobile Engineer | Tech Lead at Baycare

December 1, 2022 - Present

Mobile engineer specializing in building, scaling, and optimizing high-performance iOS and Android applications as well as cross-platform mobile apps using React Native. Delivered end-to-end architectures for healthcare, telemedicine, and IoT with focus on secure communications, offline capability, and pixel-perfect UI/UX aligned with Apple HIG and Material Design. Developed native apps using Swift, Kotlin, Jetpack Compose, SwiftUI and React Native, integrating platform SDKs like CoreBluetooth and BluetoothAdapter for real-time device connectivity. Implemented secure login flows including Face ID, Touch ID, OAuth2 and JWT. Managed RESTful API integration and established modular, testable codebases using MVVM and Clean Architecture. Designed CI/CD pipelines with Fastlane, Bitrise, Jenkins and GitHub Actions for automation and app distribution. Enhanced performance, accessibility, and app analytics to improve user engagement and stability.

Mobile Full Stack Developer at CafePress

December 31, 2022 - July 25, 2025

Contributed to development and optimization of native and hybrid mobile applications for e-commerce using Swift, Kotlin, Java, and React Native. Led development of customer-facing e-commerce apps featuring product catalogs, payment processing, order tracking, push notifications, and mobile wallets. Integrated payment gateways such as Stripe and PayPal, with support for Apple Pay and Google Pay. Used REST APIs and GraphQL for backend integration, real-time product updates, and inventory tracking. Built authentication flows via OAuth2, JWT and Firebase Authentication. Delivered performance optimizations improving app responsiveness by 30%. Developed and maintained CI/CD pipelines using Bitrise, Fastlane, and Jenkins. Worked collaboratively in Agile teams ensuring timely delivery of high-quality mobile solutions.

Native Mobile Engineer at American Express

August 31, 2017 - July 25, 2025

Developed native financial mobile platforms across Android and iOS focusing on performance, security, and user experience. Used Kotlin and Swift for real-time responsiveness and secure features like transactions, payments, push notifications, and offline syncing. Implemented end-to-end encryption with Signal Protocol and secure key management using Android Keystore and iOS Keychain complying with GDPR, CCPA, and PCI-DSS. Migrated Objective-C components to Swift, improving architecture and reducing technical debt. Designed modular API layer with GraphQL reducing API traffic and enabling offline support. Automated testing with XCTest and Espresso achieving over 90% test coverage. Supported Firebase Analytics and Crashlytics to monitor app performance and reduce crash rates by 40%. Developed backend APIs with AWS Lambda and API Gateway and containerized environments with Docker and Kubernetes. Collaborated in Agile teams to deliver secure financial features.