Available for freelance · Android Engineer
Hi, I'm Yudistiro —Android Engineer building Fintech-grade apps.
Android Developer with 7+ years of professional experience, especially in Fintech — building high-quality mobile applications with modern Android architecture and cross-platform solutions. Proven track record of reducing build time by 30% and improving user engagement by 20%+ in production apps. Skilled in Jetpack Compose, Kotlin Coroutines, and Flutter, with a strong focus on scalable, modular design and SOLID principles.
Career
Experience
7+ years building Android and mobile products across fintech, securities, insurance, e-commerce, and freelance — from SDK payment layers to real-time trading UIs.
Android Engineer
Tuntun Sekuritas
- Built Native Chart Pro, delivering advanced native charting through a modular, maintainable architecture.
- Delivered multiple Android features and modules from PRDs with high functional accuracy and close alignment to product & UI specs.
- Selected as the Android representative for the frontend AI research team, evaluating and implementing practical AI-assisted development workflows.
- Established standards for AI agents, reusable agent skills, and internal project knowledge/indexing to improve contextual accuracy across Android tasks.
- Built an Android-focused CLI connecting Jira, Confluence, Git, Figma, and Google's android-cli to streamline research, implementation, and delivery.
- Increased AI-assisted development speed by 30–40% while improving implementation consistency.
Android Engineer
New Smart Branch – Bank Mandiri
- Optimized dependency management with Gradle Version Catalogs, cutting configuration duplication by 30% across 10+ modules.
- Engineered robust pagination with Paging 3 and state preservation, reducing perceived latency by 20% across lifecycle changes.
- Conducted code reviews that raised overall code quality.
- Maintained and enhanced smart-branch features, proactively resolving production issues to sustain stability.
- Collaborated with backend, QA, and UI/UX teams to deliver feature updates on schedule.
Freelance Mobile Developer
Confidential Client
- Built and customized an AI-integrated chat app and attendance tracking system in Flutter, tailoring marketplace solutions to client needs.
- Built and maintained internal Kotlin Android apps, including a secure internal chat app and an emergency SOS reporting app.
- Enhanced an agent notes app with voice recording, speech-to-text, and text-to-speech to boost field-staff productivity.
- Implemented Single Sign-On (SSO) across all apps for unified, secure access.
- Provided ongoing bug fixing and feature enhancements, improving stability and adoption.
Android Engineer
Stockbit
- Resolved critical bugs, increasing app stability and reducing production crashes.
- Revamped withdrawal & deposit UI, improving task completion speed by 20% and aligning with Material Design 3.
- Implemented the e-Statement feature for in-app transaction summaries.
- Pioneered the first WebSocket + Protobuf implementation on Android for the Running Trade feature.
- Refactored trading features for performance and maintainability following clean-architecture principles.
Freelance Mobile Developer
Jelajah Bantul – Tourism App
- Built the app from scratch in Flutter using BLoC, Dio, and Modular architecture for scalability.
- Designed the Nearby Tourist Spots feature with real-time, location-based discovery.
- Showcased destinations with rich multimedia to improve engagement.
- Added a photo-sharing feature for a community-driven travel experience.
- Optimized data flow and caching with Dio + BLoC, reducing page load time by 30%.
Mobile Programmer
Sinarmas MSIG Life
- Maintained and optimized legacy Java apps, cutting the critical bug backlog by 40% and extending product lifecycle.
- Implemented systematic bug-resolution workflows, improving defect resolution speed by 25%.
- Helped migrate a Java CRM system to Flutter for cross-platform Android/iOS support.
- Ensured feature parity and improved UI/UX consistency, increasing CRM adoption across branches.
Freelance Android Developer
Looké Beauty – Virtual Makeup App
- Developed Looké Beauty, an Indonesian AR-powered virtual makeup try-on app published on Google Play.
- Implemented real-time AR cosmetic try-ons using Kotlin, MVVM, and Navigation Component.
- Integrated product catalog, user reviews, and beauty tips into a seamless UI.
- Optimized the AR rendering pipeline, reducing latency by 25% for smooth, realistic try-ons.
Android Engineer
Aino Indonesia
- Developed secure SDK payment solutions (chip-based & server-based, incl. GoPay), enabling 5+ enterprise integrations with 30% faster partner onboarding.
- Designed POS applications handling thousands of transactions daily with strong stability.
- Integrated SDK payment modules into EDC devices, reducing transaction failure rates by 25%.
- Created self-ordering kiosk apps integrated with POS, shortening average order time by 20%.
- Collaborated with hardware, backend, and QA teams to meet industry compliance and security standards.
Android Developer
PT Cipta Dinamika Unggul
- Architected and launched the "Kirim Bunga" marketplace app (Google Play), serving thousands of customers nationwide.
- Implemented product management, transaction monitoring, and secure payment gateways.
- Built seller dashboards with real-time order tracking, boosting seller response times by 35%.
- Optimized product catalog performance, reducing load time by 40%.
- Ensured robust fund disbursement, maintaining a 100% transaction settlement rate.
Toolbox
Skills
Core Android
Cross-platform
Architecture & Testing
Cloud & Tools
AI-Assisted Development
Tooling
Languages
Client feedback
What clients say
All reviews are from verified contracts on Upwork.
Yudis has been an outstanding developer throughout our work together. He is smart, reliable, fast, and very detail oriented.
Excellent work, great communication, and professional support. I would gladly work with him again.
As always Yudis — phenomenal work. He is one of the most skilled people I've worked with. Great job as always; we upgraded our app browser in a great way.
Yudis is great as always, helped us integrate a rating system in our app. Great work Yudis, thank you!
As always, Yudis is phenomenal — one of the smartest people I've worked with. He executes very fast, with deep understanding and great attention to detail.
Yudis is a highly experienced developer, a great listener, and very solution-oriented. He works quickly and handles problems in an efficient and professional way.
Excellent technical skills, prompt and clear communications, flexible and co-operative. Recommended!
I had a pleasure to work with Yudistiro again after working with him on previous projects. He was very helpful, patient and delivered well-written code.
I truly enjoy collaborating with this individual. After showcasing his fantastic programming skills in the previous project, I decided to go with a more advanced part of the app.
I decided to work with Yudistiro after reading a bit about his background and experience. He was very attentive to helping me figure out what was causing the problem and how to correct it.
Background
Education
Bachelor's Degree in Computer Science
STMIK Akakom Yogyakarta · now Universitas Teknologi Yogyakarta
2015 – 2020