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Are you looking for an expert Android Developer to build a high-performance, cross-platform mobile application? As a Senior Android Developer specializing in Kotlin Multiplatform (KMP) and Compose Multiplatform (CMP), I help businesses launch native-quality apps while reducing Mobile App Development costs by up to 50%. By sharing business logic across Android and iOS, I ensure your project is scalable, maintainable, and built for long-term success. 🚀 AI-Powered Android App Development Velocity I leverage an advanced AI-augmented workflow (Cursor, MCP, and Gemini/Claude) to accelerate the Mobile App Development lifecycle. This allows me to: - Code Faster: Automate boilerplate so I can focus on your app's unique architecture. - Increase Accuracy: Use AI-driven refactoring to ensure your Android App is bug-free. - Rapid Prototyping: Deliver production-ready MVPs in record time without sacrificing native performance. 🚀 Core Expertise To deliver world-class Mobile App Development, I utilize a cutting-edge tech stack: - Kotlin Multiplatform (KMP): Expert-level sharing of business logic, networking, and data layers. - Compose Multiplatform (CMP): Designing 100% shared, responsive UIs for Android, iOS, and Desktop. - Native Android: Jetpack Compose, Material 3, Coroutines, and Flow. - Architecture: MVI/MVVM Clean Architecture for scalable, testable codebases. - Smart Notifications: Implementing complex Push Notification strategies, including rich media alerts, deep-linking, and background data synchronization. 🛠️ Technical Stack - Languages: Kotlin, Java, Swift (Interop). - DI & Local Data: Koin, Hilt, SQLDelight, Room. - Networking: Ktor, OkHttp, REST, WebSockets, Apollo GraphQL. - Real-Time & Media: WebRTC (Audio/Video), Twilio, PJSIP, Jitsi, Firebase Services. - Hardware & IoT: Bluetooth (BLE), Geolocation, Maps, and Sensor integration. 💼 Why Choose Me as Your Lead Android Developer? - Top Rated Plus: 100% Job Success Rate and a veteran Android Developer of the Upwork platform. - End-to-End Delivery: From initial concept and architecture to successful Play Store/App Store deployment. - Proven Experience: Numerous commercial projects and a deep portfolio of open-source work on GitHub. - Scalable Solutions: Experience building complex features like WebRTC, Biometrics, and IoT integrations. Whether you need a Kotlin specialist to refactor an existing codebase or a Mobile App Developer to build a cross-platform solution from scratch, I provide the technical leadership your project deserves. 📩 Let’s build your next-gen mobile app. Click the "Invite to Job" button to discuss your requirements and see how my AI-augmented workflow can save you time and budget!

Hey Guys! I’m an Android Developer Kotlin dedicated to helping startups and businesses build high-performance mobile applications. Interested? Drop me a message, and I’ll show you my workflow and how I can help your project thrive! What Android Developer Kotlin Do: ⚪️ Android Kotlin Development: Creating native apps for Android using Kotlin and Java modern UI. ⚪️ App Performance: Optimization, bug fixing Android App , and improving Mobile Develop stability. ⚪️ API Integration: Working with Full Stack teams, REST APIs, and real-time features. ⚪️ App Support: Feature updates for iOS and Android, refactoring, and long-term maintenance. I build Android apps that are not just functional but ready for production. Whether you need a native Android Developer to build from scratch or a Kotlin Developer to scale your current Android App product, I ensure the code is clean and predictable. While I focus on the Android Developer Kotlin Java ecosystem, I understand the importance of cross-platform alignment with iOS, Swift, and Flutter. What I Specialize In Android App Development ✔️ Kotlin Developer expertise: Native development for Android apps. ✔️ Android Developer Kotlin Java standards: Clean Architecture, MVVM, modular structure ✔️ Jetpack components (ViewModel, LiveData, Navigation) and Android Screen Reader support. ✔️ Coroutines and background processing for Mobile Developer projects. ✔️ Room database, SQLite, and local storage. Backend & Integrations ✔️ REST API integration and data handling with Spring Boot or JSP Developer backends. ✔️ Firebase (Auth, Firestore, Push Notifications) and Marketing Cloud Developer tools. ✔️ Salesforce Marketing Cloud Developer triggers and external SDKs. ✔️ WebSockets and real-time updates for Mobile Develop solutions. UI & UX ✔️ Modern UI with XML and Jetpack Compose for any Android Developer India or global project. ✔️ Responsive layouts that match the quality of an iOS Developer or Swift specialist. ✔️ Material Design implementation for iOS Android hybrid feel when needed. ✔️ Perfect user flows, even for complex systems like Magento integrations. Testing & Stability ✔️ Debugging and performance optimization across Bulgaria and international markets. ✔️ Memory optimization and Full Stack Developer level code cleanup. ✔️ Transitioning legacy code from Java Developer to modern Kotlin. ✔️ Web Developer collaboration for seamless API handshakes. Tech Stack: ✔️ Languages: Kotlin, Java, Javascript Developer (API-side), Python Developer (Backend-side). ✔️ Platforms: Android, iOS, Flutter, React Native. ✔️ Architecture: MVVM, Clean Architecture, Full Stack. ✔️ UI: XML, Jetpack Compose, Flutter Developer insights, iOS Developer UI standards. ✔️ Database: Room, SQLite, Java Developer legacy support. ✔️ Other: Google Maps API, Payments, IOS integrations, Bulgaria localized services. Android Developer Kotlin focus on delivering Android App working apps with clear logic, stable performance, and code that is easy to maintain. Whether you are looking for a Mobile Developer or a dedicated Android Screen Reader accessibility expert, I've got you covered. Have a project in mind? Click “Invite”, share what you’re building, and I’ll let you know how I can help.

I'm the mobile app developer you're looking for! Why? I build Android and cross-platform products that ship fast, scale cleanly, and create real business value. ABOUT ME • 9+ years and 40+ apps shipped as a mobile app developer across Android, iOS, and cross-platform builds • 25 Total jobs, 100% JSS, Top Rated status, 5-star feedback as a mobile app developer on Upwork • Avg. response time 0-4 hours, ready to start within 24 hours as your mobile app developer • 500K+ downloads across 15+ published apps as an Android developer and iOS developer • 99.9% crash-free sessions, 40% fewer production crashes through Firebase and Sentry monitoring as a full stack mobile app developer • 9+ yrs. Senior Android/Kotlin Engineer, 100% JSS, Top Rated mobile app developer with 5-star feedback across 25 completed jobs • EU/US time-zone overlap, replies within 0-4 hour WHERE I DELIVER • As Android developer kotlin - 20+ native builds, 30% faster release cycles through MVVM, MVI, and Clean Architecture • As iOS developer - 10+ Swift/SwiftUI apps, 25% smoother onboarding through native iOS patterns as an iOS Android developer • As iOS Android developer - 12+ dual-platform products maintained from a single codebase, cutting maintenance cost by 35% • As app developer iOS Android - 8+ cross-platform launches, 4-6 weeks faster time-to-market than building two native teams • As flutter developer and react native specialist - 6+ cross-platform apps, 20% lower dev cost vs. separate native builds • As full stack developer and web developer - 10+ backend APIs and admin dashboards powering every mobile app developer stack end-to-end • As ai mobile app developer - 5+ AI-powered features shipped (voice, vision, LLM), cutting manual workflows by 40% • As Android game developer - 3+ Unity-integrated apps with real-time rendering and physics • As mobile developer and app developer iOS - 15+ App Store and Google Play submissions handled start to finish INDUSTRY IMPACT • GPS & Navigation - 6+ live-tracking map apps, 99.5% location accuracy, powering fleet and delivery use cases as a mobile app developer • Warehouse & Inventory - 4+ barcode-scanning apps built on Zebra SDK, cutting inventory errors by 30% and pick times by 25% as an Android developer • Retail & Hospitality Kiosks - 3+ self-service kiosk apps handling 1,000+ daily transactions each as a mobile app developer • Voice & Speech - 3+ speech-recognition apps with 95%+ transcription accuracy as an ai mobile app developer • Proximity & BLE - 5+ beacon-based apps improving proximity detection accuracy by 25% as an Android developer kotlin specialist • Full Stack Delivery - 10+ end-to-end builds spanning backend, web developer dashboards, and mobile clients as a full stack mobile app developer TYPES OF APPS I'VE BUILT • 15+ GPS-enabled map apps with live location tracking and turn-by-turn navigation as a mobile app developer • 4+ warehouse management apps with barcode scanning and real-time inventory sync as an Android developer kotlin specialist • 3+ kiosk apps for retail, hospitality, and self-service terminals processing 1,000+ transactions daily • 3+ speech-recognition and voice-to-text apps with 95%+ transcription accuracy as an ai mobile app developer • 5+ BLE beacon and proximity-detection apps as an Android developer, plus 3+ Unity-integrated builds as an Android game developer • 6+ cross-platform apps as a flutter developer, and 2+ additional flutter developer rebuilds migrating legacy hybrid apps to native performance • 8+ camera-focused media capture tools and 5+ AI-powered conversational interfaces as an app developer iOS Android HOW I BUILD • 20+ CI/CD pipelines configured, 35% faster build and release cycles as a mobile app developer • Kotlin, Java, Swift, Flutter, React Native - 40+ apps delivered across Android developer, iOS developer, and app developer iOS Android engagements • Jetpack Compose, RxJava, Coroutines, Dagger, Hilt, Koin, MVVM, MVI - core toolkit for every mobile developer and full stack mobile app developer build • Firebase, Android Profiler, Sentry, custom analytics - 99.9% crash-free sessions across 15+ live apps as a mobile app developer • Git, Jenkins, Jira, automated test coverage - structured delivery as a full stack developer and app developer iOS for teams of any size • GPS/Location Services, Google Maps SDK, Speech Recognition, BLE, Unity, Zebra SDK - hardware depth that sets an iOS Android developer apart from a generic app developer Clients keep hiring me as their mobile app developer because the numbers hold up: 9+ years of experience, 25 Total jobs, 100% JSS, Top Rated status, 5-star feedback, and a 0-4 hour response time. Whether you need an Android developer for a native build, an iOS developer for App Store polish, an app developer iOS Android team for a dual-platform launch, or an ai mobile app developer to add intelligent features - I'm ready to contribute from day one. 📩 Let's build something robust, and engineered to last.

🚀 I am Andriy, a Senior Mobile App Developer with over 4 years of professional experience delivering high-quality mobile and web solutions for startups, growing companies, and enterprise clients. As a Mobile App Developer and Full Stack Developer, I specialize in building scalable, user-friendly, and high-performance applications for both mobile and web platforms using modern frameworks such as Flutter and web technologies. My work is focused on turning business ideas into reliable digital products that create real value for users and support long-term business growth. My skills: React Native Mobile App Development iOS Development Android App Development AI Mobile App Development Hybrid App Development App Development Flutter Mobile App Design Web Development Android Software Development Firebase React Artificial Intelligence Native App Development Kotlin Mobile App Development Consultation Smartphone Mobile App 💡 Throughout my career, I have worked on a wide range of projects across different industries as a Mobile App Developer and Full Stack Developer. My experience allows me to build modern, responsive, and intuitive applications with strong performance across platforms. As a Flutter Developer, I create visually polished apps with clean architecture, smooth animations, and strong functionality. Every project I take on is approached with attention to detail, code quality, and user experience. 🌍 My background includes work in industries such as social media, healthcare, education, manufacturing, automotive, finance, legal, sales, sports, and AI-powered products. I have built social platforms with interactive user flows, healthcare apps with secure data handling, finance products with reliable performance, and educational apps that make learning more engaging. As a Mobile App Developer and Full Stack Developer, I always adapt technical solutions to the unique needs of each business domain. 👨‍💻 I currently lead a professional team at JoinToIT in Kyiv, Ukraine, where we provide full-cycle mobile and web development services. Our team includes experienced specialists working as Mobile App Developers, Full Stack Developers, and Flutter Developers, and we collaborate closely to deliver high-quality products from concept to release. I understand how important communication, planning, and flexibility are during the development process, so we combine technical skills, creative thinking, and agile methodologies to ensure project success. ⚙️ I can support every stage of the product lifecycle: requirements analysis, architecture planning, UI/UX collaboration, app and web development, API integration, testing, debugging, deployment, and post-launch maintenance. My goal is not only to write clean code, but also to help clients make smart product decisions. A strong developer should think beyond implementation and focus on business goals, usability, performance, and scalability. 🧩 My technical stack includes Flutter, React, web technologies, Node.js, Firebase, MySQL, and API development using PHP Laravel, Node.js, and Python. I also have strong experience with third-party integrations, including Stripe, PayPal, Twilio, TextMagic, Xero, DocuSign, Google Maps, Facebook, Instagram, Twitter, and HelloSign. I understand how essential it is to build apps and web platforms that integrate smoothly with modern services. 📈 I take pride in being a developer who values reliability, transparency, and long-term results. I am always open to feedback, continuous improvement, and adopting new technologies that enhance product quality. Whether you need a Mobile App Developer, a Full Stack Developer, or a Flutter Developer, I can help build a solution that is modern, stable, and ready for growth. 🤝 As a Senior Mobile App Developer and Full Stack Developer, I am committed to creating applications that exceed expectations, deliver real business value, and provide seamless user experiences across both mobile and web platforms. Best regards, Andriy

As Android App Developer / Kotlin Developer with 10 years of experience I'm helping small businesses, startups, and indie founders translate their vision into scalable, high-performance apps from 0 to launch, make MVP in weeks, integrate on-device AI and upgrade apps to comply with the latest Google Play requirements. In 2026 I specialize in: - on-device AI integration using MediaPipe / LiteRT / Google ML Kit ( Object detecton , Face detection , Pose detection , Text summarizing / OCR , text-to-speech , speech-to-text ); - video / media editing apps ( FFMpeg , AndroidX Media3 ); - building media , social , and productivity tools (not games); - fixing app performance , memory leaks , crashes and ANRs , especially in complex or “vibe-coded” apps. 🌟🌟🌟🌟🌟 Recent feedback : "I was particularly impressed by his strong attention to detail - nothing was overlooked, and the quality of the work consistently met high standards. He showed real commitment to the project, staying engaged and proactive throughout the development process. His regularity and consistency in delivering work made collaboration smooth and reliable." - Neil 🚀 Also I've been building my own Android apps so that gives me a deep understanding of not only a technical part but also ASO and monetization strategy. ✅️ Recent large-scale projects: --- PDF Maker & Reader (130k+ installs , 🌟4.6 on Google Play) Role: Android Developer / Android App Developer / Kotlin Developer I recently built this high-performance Android app from scratch based on Figma mockup using Kotlin. It allows users to quickly convert images to PDF and edit existing PDFs using a fast, local-first architecture. The app has achieved 130k+ downloads and 8k monthly active users on Google Play, with the crash rate lower than 0.1%. --- --- US Medical Education App (COMQUEST for COMLEX & COMAT Prep) Role: Android Developer / Android App Developer / Mobile Developer As part of an international team alongside iOS Developer and Web Developer, I built this Android app from scratch based on Figma designs for US medical students. Continue providing ongoing support for this project, ensuring the mobile app remains a stable and reliable tool for users. --- --- US Automotive Video Suite app Role: Android Developer / Android App Developer / Mobile Developer In collaborating with an iOS Developer and a Full Stack Developer, I built two native Android apps from scratch as a clone of iOS apps (Dealer Video Inventory and Dealer Video Suite) that allows dealers to capture high-quality vehicle inventory videos and photos. These projects helps dealers increase sales through personalized video. --- 🌟 🌟🌟🌟🌟 "Dmitri is a pleasure to work with. He's Android programming skills are exceptional. He's always professional and easy to work with. He is very methodical in his approach. Which at times has resulted in delivery scheduling slipping a little but I rather have a good product than a hastily put together product. We're continuing to work with Dima for other projects." - Philip Whether you are looking for a Mobile Developer to lead a new project or an Android Developer to optimize an existing Java / Kotlin codebase or optimize performance, my goal is to provide technical clarity and long-term stability. As a team player for cross-platform projects I have a proven track record of working alongside iOS developers to ensure smooth releases. I also have specific experience collaborating with Flutter Developers and Full Stack Developers to bridge the gap between cross-platform Flutter / React Native code and the system features specifically by developing custom Java / Kotlin modules to handle native Android OS functionality that standard Flutter plugins can't reach. --- 🚀 My core stack: 🔸️Languages: Java , Kotlin 🔸️UI: XML , Jetpack Compose 🔸️Architecture: MVVM , MVI , Clean Architecture 🔸️Native: Android SDK , Android Studio 🔸️Multiplatform: Kotlin Multiplatform ( KMM / KMP ) / Compose Multiplatform ( CMP ) 🔸️Key features: Camera , Photo & Video capture and edit using FFMpeg , OpenGL , OpenCV ; GPS , Location , Chat , Background syncronization , WorkManager and foreground services, ofline-first approach, on-device AI / LLM , VPN / WireGuard , ExoPlayer / Media3 🔸️On-device AI integration : Video analysis , Image recognition , Object detection , Face detection , Pose Detection , Camera stream analysis , Text-to-Speech , Speech-to-Text ( MediaPipe / Google AI Edge , TensorFlow / TFLite , Google ML kit ). 🔸️Cloud AI integration : OpenAI , Gemini API

Mobile app developer with 14+ years of mobile app development, 80+ apps shipped, and a Flutter app past 2M+ users. ⭐ Top Rated on Upwork since 2018 · 5.0 on Clutch · 4.93 on GoodFirms If you're starting a Flutter app from scratch, I take it from concept to the App Store. If your iOS or Android app has stalled, I get it shipping again. If a previous mobile app developer missed what you actually needed, that's where I usually come in. 𝗪𝗵𝗮𝘁 𝘆𝗼𝘂 𝗴𝗲𝘁 ✔️ As a Flutter developer I ship one codebase to iOS and Android at once, up to 40% cheaper than two native builds. ✔️ The mobile app design and the mobile app development come from the same person. No handoffs, no two contractors blaming each other. ✔️ Healthcare apps that pass HIPAA and GDPR. Logistics apps that keep working when the signal drops. ✔️ Hire the wrong mobile app developer and the scope gaps surface at the first build. I flag them earlier, and clients have brought me in to redo exactly that. ✔️ 80+ apps in, I have already hit the problems your build will run into. One app I built passed 2M+ users. Send me what you're building and I'll reply with a scope estimate and the first technical decision I'd settle. Clients come back a year in after hiring the wrong mobile app developer first; early hires save months. 𝗥𝗲𝗮𝗱𝘆 𝘄𝗵𝗲𝗻 𝘆𝗼𝘂 𝗮𝗿𝗲 Best, Stan ————— Selected work and skills: HEALTHCARE APP DEVELOPMENT, 25+ projects - Healthcare App Developer, Secure Care UK medical transport: 5,000+ secure patient transfers a year across a 25+ vehicle fleet and a 24/7 control room. - HIPAA Developer, secure PHI handling for 5,000+ patient records - HL7 FHIR syncing records across 3 hospital systems - GDPR compliance on 100% of builds - Healthcare Apps prompting status updates every 30 minutes across 4 job levels - Healthcare SaaS development, Secure Care UK: replaced a third-party subscriber platform, cutting running costs $3,000+ a month. - Full Stack Developer Healthcare, Secure Care UK across web and mobile: 5,000+ transfers coordinated from one system. - Flutter developer, Patient Gateway UK medical transport: Firebase sync and real-time driver tracking with dispatch updates under 5 seconds. - Flutter Developer, Rheo health wearable: 5 vital-sign categories streamed over LTE in real time, secure PHI handling tested across iOS, Android, and web. - Mobile App Developer, fertility health app: bug-free rate raised 85% to 96% in a two-week retest, delivered in 3 months against a 4-month estimate. LOGISTICS APP DEVELOPMENT, 20+ projects - Logistics App Developer, last-mile delivery app: satisfaction raised 35% to 85%, wait times cut 34% in low-signal areas, 12 partners signed in 3 months. MOBILE APP DEVELOPMENT, 80+ apps - Flutter developer, mobile app development: 30+ Flutter projects, build cycles cut 50% and costs 40% versus native through Flutter development. - Flutter App Developer, Ziroop: 2 app stores from one Flutter codebase, 50,000+ installs in year one. - Mobile App Developer, Quran learning app: 2M+ users, rebuilt in 4 months. - Flutter Developer, government train ticketing app: shipped in 6 months against a 7-month deadline, NFC storing 5 tickets offline across 20 screens. - iOS Developer and Swift iOS Developer: native iOS apps shipped since 2012 in Swift, one rebuilt to full feature parity in 8 weeks. - Android App Developer: rebuilt an unstable Android app, crashes cut 90% and store rating lifted to 4.7. - Mobile app developer, Android Developer and Mobile Developer: native and cross-platform mobile development across 80+ apps. FULL STACK - Full Stack Developer: 150+ products shipped end to end, frontend, backend, and database. - Full Stack Mobile Developer: frontend plus backend on 30+ products, delivered end to end. MOBILE APP DESIGN, 40+ designs - Mobile app designer, mobile app design: 70+ wireframes and 40+ mobile app designs, engagement up 40%. - Mobile UI UX Design: consistent UI across both platforms on 40+ screens, task completion up 30%. - Mobile App UI UX Design in Figma: Figma App Design and Figma Mobile App Designer work across 35+ flows. REACT NATIVE - React Native Developer and React Native Development: 10+ React Native apps on the App Store and Google Play as a React Native Developer Expo, React Native App Developer, and React Native Expert, spanning React Native Expo, React Native iOS, React Native Firebase, and React Native UI UX, with 12-19% better repeat usage. MORE - AI App Developer and AI Mobile App Developer: AI Mobile App Development adding on-device intelligence that cut manual work 60%. FlutterFlow developer prototypes built 3x faster in FlutterFlow. Full Stack App Developer with Python and Wordpress backends, React Native, and mobile React apps across 30+ products. SKILLS: iOS Development, Android App Development, Swift, Node.js, PHP, JavaScript, Java, Desktop Application, Web Design.