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Hi, I'm Justin! With over 7.5 years of experience in Android development, I specialize in building seamless, high-performance mobile applications using Kotlin and Java. I love collaborating with cross-functional teams to turn innovative ideas into intuitive user experiences, utilizing tools like Jetpack Compose and AWS integration. I'm passionate about writing clean, maintainable code and continuously improving app responsiveness with technologies like Kotlin coroutines and MVVM architecture. Whether mentoring junior developers, optimizing build times, or handling complex backend integrations, I’m always eager to tackle new challenges and help deliver top-quality apps.…Hi, I'm Justin! With over 7.5 years of experience in Android development, I specialize in building seamless, high-performance mobile applications using Kotlin and Java. I love collaborating with cross-functional teams to turn innovative ideas into intuitive user experiences, utilizing tools like Jetpack Compose and AWS integration. I'm passionate about writing clean, maintainable code and continuously improving app responsiveness with technologies like Kotlin coroutines and MVVM architecture. Whether mentoring junior developers, optimizing build times, or handling complex backend integrations, I’m always eager to tackle new challenges and help deliver top-quality apps.

Justin M

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Hi, I'm Justin! With over 7.5 years of experience in Android development, I specialize in building seamless, high-performance mobile applications using Kotlin and Java. I love collaborating with cross-functional teams to turn innovative ideas into intuitive user experiences, utilizing tools like Jetpack Compose and AWS integration. I'm passionate about writing clean, maintainable code and continuously improving app responsiveness with technologies like Kotlin coroutines and MVVM architecture. Whether mentoring junior developers, optimizing build times, or handling complex backend integrations, I’m always eager to tackle new challenges and help deliver top-quality apps.…Hi, I'm Justin! With over 7.5 years of experience in Android development, I specialize in building seamless, high-performance mobile applications using Kotlin and Java. I love collaborating with cross-functional teams to turn innovative ideas into intuitive user experiences, utilizing tools like Jetpack Compose and AWS integration. I'm passionate about writing clean, maintainable code and continuously improving app responsiveness with technologies like Kotlin coroutines and MVVM architecture. Whether mentoring junior developers, optimizing build times, or handling complex backend integrations, I’m always eager to tackle new challenges and help deliver top-quality apps.

Available to hire

Hi, I’m Justin! With over 7.5 years of experience in Android development, I specialize in building seamless, high-performance mobile applications using Kotlin and Java. I love collaborating with cross-functional teams to turn innovative ideas into intuitive user experiences, utilizing tools like Jetpack Compose and AWS integration.

I’m passionate about writing clean, maintainable code and continuously improving app responsiveness with technologies like Kotlin coroutines and MVVM architecture. Whether mentoring junior developers, optimizing build times, or handling complex backend integrations, I’m always eager to tackle new challenges and help deliver top-quality apps.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

Javanese

Advanced

Work Experience

Senior Android Developer at T-Mobile US, Inc.

October 1, 2024 - Present

Owned Jetpack Compose feature work for the T-Life (ScamShield 2.0) redesign, crafting modular composables following T-Mobile design-system tokens. Collaborated cross-functionally with Product, UX, QA, and backend teams to break down user stories and deliver new features each sprint. Integrated Firebase Crashlytics for real-time monitoring and fixed issues promptly. Implemented MVVM with Coroutine + Flow ensuring lifecycle-aware and testable ViewModels. Maintained CI/CD pipelines using Bitrise & Jenkins. Instrumented analytics events to drive product decisions. Enforced app security compliance with runtime permission flows. Optimized build times significantly through modularization and caching. Mentored junior developers and supported post-launch maintenance, achieving a 4.7 rating on latest release.

Senior Android Developer at AT & T

October 1, 2024 - July 16, 2025

Led full lifecycle of Android app development from design to deployment, prioritizing user-centered design and performance optimization. Proficient in Kotlin, Java, Android SDK, Android Studio, Git, and Gradle. Conducted code reviews and mentorship to uphold code quality. Worked with product managers and UX/UI teams to align technical solutions with business goals. Integrated third-party APIs to extend functionality. Leveraged Jetpack components to streamline architecture and implemented asynchronous programming with coroutines and RxJava. Applied Android security best practices to protect user data.

Android Developer at T-Mobile

July 1, 2021 - July 16, 2025

Designed and developed Android applications focusing on functionality and smooth user experience. Enhanced real-time video streaming performance focused on H.264 and H.265 codecs. Conducted detailed code reviews and collaborated with product and UX/UI teams to align technology with business objectives. Integrated backend APIs and applied Agile methodologies for project management and team collaboration.

Android Developer at Capital One

May 31, 2018 - July 16, 2025

Developed Android apps using Kotlin with suspending functions and coroutines for API calls and background tasks. Worked with Jetpack Compose to improve development efficiency and UI declarative design. Integrated third-party APIs including payment gateways and analytics. Participated in Agile scrum calls and delivered Jira tickets with GitHub code reviews. Enhanced app features such as real-time transaction monitoring and biometric authentication. Led networking stack migration and improved RecyclerView scroll performance.