Darko P.

Senior Android & Flutter Developer | Mobile Architect | Kotlin, Jetpack Compose & Dart 13+ Years Android Experience | Production Flutter Experience | Top Rated | 100% Job Success Looking for an experienced mobile developer who can build a high-quality application, modernize an existing product, or solve complex architecture and performance challenges? I'm a Senior Android & Flutter Developer and Mobile Architect with 13+ years of professional Android experience and hands-on experience developing and leading production Flutter applications. My background includes applications serving hundreds of millions of users, secure payment SDKs, enterprise mobile platforms, and IoT solutions. I combine hands-on development with architecture and technical leadership to deliver reliable, scalable, and maintainable products. What I Can Help You With Android Development - Kotlin, Java, Jetpack Compose, Coroutines, Flow - MVVM, MVI, Clean Architecture - Room, Retrofit, Hilt/Dagger - Java-to-Kotlin and XML-to-Compose migrations - Performance optimization, ANR reduction, and refactoring Flutter Development - Flutter and Dart for Android and iOS - Riverpod, Bloc/Cubit, Clean Architecture - REST APIs, authentication, and Firebase - Localization and responsive UI implementation - CI/CD automation and production deployments Mobile Architecture & Technical Leadership - Scalable and modular application architecture - Android SDK and reusable library development - Secure authentication and payment integrations - Bluetooth Low Energy (BLE) and IoT connectivity - White-label mobile application platforms - Code reviews, mentoring, and technical leadership Selected Projects and Results Truecaller — Senior Android Engineer Contributed to the modernization of an Android application with over 500 million users worldwide. - Migrated legacy Java and XML components to Kotlin and Jetpack Compose. - Worked on reducing Application Not Responding (ANR) issues and improving application stability. - Improved code maintainability through modern Android architecture, refactoring, and automated testing. - Delivered changes within a mature, large-scale production codebase where reliability and backward compatibility were essential. LMT Latvia — Mobile Technical Lead (Flutter) Led mobile engineering for a production Flutter-based IoT platform. - Established feature-first Clean Architecture using Flutter, Dart, and Riverpod/Cubit. - Developed reusable components and structured API integrations using Dio. - Integrated secure authentication using Auth0 and PKCE. - Implemented localization, testing practices, and CI/CD workflows using Codemagic. - Improved development consistency and maintainability through shared architectural patterns and engineering standards. WSAudiology — Senior Mobile Developer / Product Architect Contributed to mobile platform development and architectural decisions across four development teams. - Designed and maintained reusable mobile components and SDK functionality. - Supported white-label application architecture, enabling functionality to be shared across multiple mobile products. - Developed analytics and event-tracking integrations to support product insights. - Helped establish consistent architecture and development practices across teams. - Collaborated with engineers and stakeholders to improve code reuse and long-term maintainability. Netcetera — Senior Android Developer Developed security-sensitive Android solutions for enterprise and financial applications. - Worked on 3-D Secure (3DS) SDK functionality used in banking and payment authentication solutions. - Implemented secure communication mechanisms, including certificate pinning. - Contributed to enterprise mobile projects requiring strong security and reliability. - Developed reusable components and supported integration into larger client applications. Independent Mobile App Developer — MelioAppStudio I independently develop, publish, and maintain Android and iOS applications under MelioAppStudio. - Successfully launched multiple consumer applications on Google Play and the Apple App Store. - Managed the complete development lifecycle, from initial architecture and implementation to testing, publishing, and maintenance. - Implemented localization for international markets, in-app purchases, subscriptions, advertising, and analytics. - Used real-world user feedback and application performance data to prioritize improvements and new features. - Gained firsthand experience with the business and technical challenges of delivering consumer mobile products. Why Work With Me? - Top Rated Upwork freelancer with 100% Job Success - 48 completed Upwork jobs and over 3,300 hours worked - More than $60,000 earned through Upwork projects - 13+ years of professional Android development - Experience contributing to applications serving 500M+ users - Technical leadership experience across multiple development teams - Hands-on production experience with b