Hi there! I’m James, a Senior Mobile Engineer with 11 years of experience building high-performance iOS and Android apps across healthcare, finance, and consumer tech. I specialize in React Native, Flutter, Kotlin, Swift, and Objective-C, with strong backend integration in Java and Python. I love turning complex problems into delightful user experiences and robust cross-platform solutions. As a builder and mentor, I design scalable mobile foundations, lead end-to-end features, and collaborate closely with backend teams to align APIs and data models. I’m passionate about accessibility, performance, and data-driven decisions that improve patient care, driver efficiency, and user engagement.…

James Wesley Harrison

Hi there! I’m James, a Senior Mobile Engineer with 11 years of experience building high-performance iOS and Android apps across healthcare, finance, and consumer tech. I specialize in React Native, Flutter, Kotlin, Swift, and Objective-C, with strong backend integration in Java and Python. I love turning complex problems into delightful user experiences and robust cross-platform solutions. As a builder and mentor, I design scalable mobile foundations, lead end-to-end features, and collaborate closely with backend teams to align APIs and data models. I’m passionate about accessibility, performance, and data-driven decisions that improve patient care, driver efficiency, and user engagement.…

Available to hire

Hi there! I’m James, a Senior Mobile Engineer with 11 years of experience building high-performance iOS and Android apps across healthcare, finance, and consumer tech. I specialize in React Native, Flutter, Kotlin, Swift, and Objective-C, with strong backend integration in Java and Python. I love turning complex problems into delightful user experiences and robust cross-platform solutions.

As a builder and mentor, I design scalable mobile foundations, lead end-to-end features, and collaborate closely with backend teams to align APIs and data models. I’m passionate about accessibility, performance, and data-driven decisions that improve patient care, driver efficiency, and user engagement.

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Skills

Experience Level

React Native
Expert
AWS
Expert
Swift
Expert
JavaScript
Expert
GraphQL
Expert
Flutter
Expert
TypeScript
Expert
Java
Expert
Docker
Expert
Kubernetes
Expert
Android
Expert
Dart
Expert
Python
Expert
iOS
Expert
Kotlin
Expert
Objective-C
Expert
DynamoDB
Expert
MongoDB
Expert
PostgreSQL
Expert
MySQL
Expert
Jira
Expert
Github
Expert
Ionic
Expert
SQLite
Expert
Google Cloud
Expert
SQL
Expert
Express
Intermediate
AngularJS
Intermediate
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Language

English
Fluent

Work Experience

Senior Mobile Engineer at DigitalFish
September 1, 2025 - September 16, 2025
Led development of a cross-platform mobile app for doctor appointments and medical decision support using React Native, with native accessibility features (VoiceOver, TalkBack) to ensure inclusive UX. Implemented GraphQL-backed data querying, GraphQL integrations with React Native and Flutter, and advanced networking with REST APIs and offline caching. Managed app store deployments (TestFlight) with feedback from 1,000+ testers, reducing post-launch issues by 40%, and cut customer acquisition costs by 30% via Firebase Analytics insights. Automated build/deploy pipelines with Fastlane and Python scripts, reducing manual deployment time by over 50%. Introduced Expo for rapid cross-platform development and improved test automation (Jest, Mocha, XCTest) for reliability. Collaborated across teams to design robust APIs, improve performance, and ensure scalable backend integration.
Mobile Application Developer at Maximum Transportation
April 1, 2022 - September 16, 2025
Designed and built a fleet management and rider scheduling app using React Native and Kotlin, featuring real-time driver tracking, route optimization, and rider notifications. Built serverless backends with AWS Lambda, API Gateway, and DynamoDB to handle thousands of trip requests with near real-time latency and offline-first capabilities using SQLite. Integrated payments and digital wallets to increase rider adoption by 20%. Led beta testing via TestFlight and Google Play, driving a 25% increase in user satisfaction. Implemented a voice-based social platform for community engagement and developed core audio components to streamline cross-platform development.
Mobile Developer at InfoBeyond Technology LLC
August 1, 2017 - September 16, 2025
Directed development of an instant messaging app with end-to-end encryption (Signal Protocol), ensuring GDPR/CCPA compliance. Migrated legacy REST APIs to GraphQL, reducing API calls by 40% and improving backend flexibility. Built unit/integration/UI tests (Espresso, XCTest) and migrated Objective-C code to Swift for modernized maintenance. Leveraged Firebase for analytics and crash reporting, reducing crash rates by 40%, and introduced Docker/Kubernetes in the development lifecycle to improve deployment reliability and speed. Fostered cross-functional collaboration using Agile practices and Jira.

Education

Bachelor of Science in Computer Science at Western Kentucky University
August 19, 2008 - August 23, 2012

Qualifications

FullStack Certification – React Native
September 26, 2025 - September 25, 2026

Industry Experience

Healthcare, Software & Internet, Transportation & Logistics
    paper Real-Time Encrypted Messaging App

    Developed a feature-rich instant messaging application tailored for community groups, using Kotlin for Android, Objective-C for iOS and successfully deployed the app on both Android and iOS platforms, achieving a user base of over 10,000 within the first six months after launch.

    paper Transportation & Rider Management App

    Built a cross-platform fleet and rider management app with real-time tracking, route optimization, offline-first capabilities, and serverless AWS backend, improving on-time arrivals by 35% and boosting rider adoption by 20%.

    paper Healthcare Appointment & Clinical Support App

    Created a mobile application aimed at assisting doctors in making informed clinical decisions, using React Native for hybrid platform and contributed to a 20% improvement in diagnostic accuracy and a 30% reduction in time spent per consultation, as reported by the client.

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