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I am a software engineer specializing in mobile development for iOS and Android, with a passion for building scalable, user-focused apps using Kotlin, Swift, Flutter, and React Native, plus experience with PHP, Django, and React. I love collaborating across teams to deliver clean, maintainable code and high-quality software across diverse industries. I’m known for strong collaboration, mentoring junior developers, and delivering reliable solutions. I enjoy tackling complex problems, optimizing performance, and ensuring accessibility and usability in every product I work on.…I am a software engineer specializing in mobile development for iOS and Android, with a passion for building scalable, user-focused apps using Kotlin, Swift, Flutter, and React Native, plus experience with PHP, Django, and React. I love collaborating across teams to deliver clean, maintainable code and high-quality software across diverse industries. I’m known for strong collaboration, mentoring junior developers, and delivering reliable solutions. I enjoy tackling complex problems, optimizing performance, and ensuring accessibility and usability in every product I work on.

John Ray Guerra

Web Developer, Full Stack Developer, App Developer, +2

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I am a software engineer specializing in mobile development for iOS and Android, with a passion for building scalable, user-focused apps using Kotlin, Swift, Flutter, and React Native, plus experience with PHP, Django, and React. I love collaborating across teams to deliver clean, maintainable code and high-quality software across diverse industries. I’m known for strong collaboration, mentoring junior developers, and delivering reliable solutions. I enjoy tackling complex problems, optimizing performance, and ensuring accessibility and usability in every product I work on.…I am a software engineer specializing in mobile development for iOS and Android, with a passion for building scalable, user-focused apps using Kotlin, Swift, Flutter, and React Native, plus experience with PHP, Django, and React. I love collaborating across teams to deliver clean, maintainable code and high-quality software across diverse industries. I’m known for strong collaboration, mentoring junior developers, and delivering reliable solutions. I enjoy tackling complex problems, optimizing performance, and ensuring accessibility and usability in every product I work on.

Available to hire

I am a software engineer specializing in mobile development for iOS and Android, with a passion for building scalable, user-focused apps using Kotlin, Swift, Flutter, and React Native, plus experience with PHP, Django, and React. I love collaborating across teams to deliver clean, maintainable code and high-quality software across diverse industries.

I’m known for strong collaboration, mentoring junior developers, and delivering reliable solutions. I enjoy tackling complex problems, optimizing performance, and ensuring accessibility and usability in every product I work on.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Work Experience

Tech Lead / Mobile Developer at OANDA Coinpass

January 1, 2020 - November 14, 2025

Overseeing mobile development for Coinpass iOS and Android apps, ensuring delivery of secure, scalable, and user-focused cryptocurrency trading experiences. Migrated from React Native to fully native Kotlin and Swift, improving app performance and stability. Defined and maintained mobile architecture and coding standards across the team. Collaborated with backend, QA, and design to streamline release workflows and enhance product reliability. Mentored junior developers and facilitated technical discussions to align mobile initiatives with product goals. Integrated analytics and monitoring tools for better user insights and app performance tracking.

Mobile & Web Software Engineer at Aviation Safety Management Inc.

February 1, 2025 - February 1, 2025

Developed and maintained aviation safety and compliance mobile and web applications, ensuring data accuracy, usability, and reliability in offline and secure environments. Maintained and enhanced the company’s web platform (SERA) using PHP and JavaScript; developed a cross-platform mobile app from the ground up using React Native with custom endpoints and PHP-based APIs. Implemented robust error handling and performance optimizations to reduce crashes and improve user satisfaction. Enhanced UI consistency and accessibility based on pilot and safety officer feedback. Mentored junior developers and contributed to both web and mobile development for compliant aviation safety management solutions.

Full Stack Web Developer

September 1, 2022 - September 1, 2022

Designed and built RF Products Search Tool (RF Backdoor): a centralized web application aggregating RF product data into a searchable interface. Implemented automated web scraping and crawling pipelines using Scrapy to collect and update product information. Developed frontend with React and backend with Django, ensuring seamless integration and responsive UX. Improved search speed and reliability through strategic database indexing, query optimization, and caching mechanisms.