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I build high-performance mobile and web applications that scale — from early-stage MVPs to enterprise-grade platforms. With 10+ years of hands-on experience across Flutter, iOS (Swift), Android (Kotlin), React Native, and full-stack backends, I've helped startups, scale-ups, and enterprises ship products users love. Whether you need a cross-platform mobile app, an AI-powered SaaS product, a real-time streaming platform, or a scalable backend, I deliver clean, maintainable code with clear communication throughout. ━━━━━━━━━━━━━━━━━━━━━━━━ ✅ WHAT I BUILD ━━━━━━━━━━━━━━━━━━━━━━━━ → Mobile Apps (Flutter, iOS, Android, React Native) → AI-Powered Apps (GPT-4/5, Claude AI, OpenAI API, Chatbots) → SaaS & Subscription Platforms (Multi-tenant, billing, admin) → Real-Time Video & Live Streaming Apps (WebRTC, Agora, Twilio) → On-Demand Apps (Taxi, Food Delivery, Booking, Marketplace) → E-Commerce & Marketplace Platforms → E-Learning & EdTech Applications → IoT & BLE-Based Mobile Apps → No-Code / Low-Code (Bubble, FlutterFlow, Webflow) ━━━━━━━━━━━━━━━━━━━━━━━━ 🛠 TECH STACK ━━━━━━━━━━━━━━━━━━━━━━━━ Mobile: Flutter · Swift · Kotlin · React Native Backend: Node.js · NestJS · Laravel · Express · Firebase Frontend: React.js · Next.js · Angular Databases: MySQL · MongoDB · PostgreSQL · DynamoDB · Firestore Cloud: AWS (Lambda, API Gateway) · Firebase · GCP Payments: Stripe · PayPal · Razorpay · Braintree Real-Time: Socket. IO · WebRTC · Twilio · Firebase RTDB Maps: Google Maps · Apple MapKit · GPS Tracking ━━━━━━━━━━━━━━━━━━━━━━━━ 🎯 WHY CLIENTS CHOOSE ME ━━━━━━━━━━━━━━━━━━━━━━━━ ✔ Full ownership & IP rights from day one (your GitHub, your code) ✔ App Store & Google Play deployment handled end-to-end ✔ 6 months free post-launch maintenance ✔ Agile/Scrum process with regular updates & demos ✔ Strict adherence to Apple & Google guidelines ✔ Free 15–30 min consultation before any engagement Let's talk about your project. Message me today.

Hey! I'm Mykyta a mobile app developer, react native developer, and full stack developer with 10+ years of experience and 32 successfully released apps. My specialty is end-to-end mobile app development and creating high-performance cross-platform applications for wellness companies, startup projects, and SaaS businesses that actually move the needle. One of my apps earned App of the Day on the App Store. Another helped a startup raise $750k in seed funding. I've scaled products to 100K+ active users and consistently delivered 30%+ growth in user retention. That's not a pitch - that's a track record. 🏄 Why I'm the React Native Expert You're Looking For As a mobile developer, I build apps that feel truly native, not like a cross-platform compromise. Whether you're comparing React Native vs Flutter, need a hybrid approach, or want a flutter developer perspective to make the right framework choice, I help you pick the stack that fits your goals, timeline, and budget. I've shipped apps across iOS and Android using react native, Expo, TypeScript, and JavaScript, handling everything from architecture to App Store deployment. 💻 Full Stack Developer & Web Developer End-to-End Ownership As a full stack developer, I don't just hand off a mobile app and disappear. I own the entire product lifecycle, from web app development to mobile deployment: - Mobile: React Native, Expo, TypeScript, JavaScript, React Navigation, Redux/Flux, GraphQL, Axios, Reanimated, Lottie, Animated, i18Next - Backend & Cloud: Node.js, Nest.js, AWS, Firebase, Supabase, PostgreSQL, MongoDB - APIs, Analytics & Media: Stripe, PayPal, Segment, Appsflyer, DataDog, Sentry, WebRTC, Chart, Image Crop, Video, Push notifications - Auth, Security & Core: Firebase Auth, Auth0, Supabase, KYC/Onfido, React Native Gesture Handler, Device Info, Google Services - DevOps: CI/CD pipelines, Docker, AWS S3, CodePush, Appcenter As a react developer and nextjs developer as well, I complement every mobile product with robust React / Next.js frontends and Node.js-powered backends, so you get one partner for the full stack, not an agency or five freelancers you have to coordinate. 🤖 AI-Powered App Development AI is no longer optional. I build intelligent mobile features that feel natural - LLM integrations, smart recommendations, predictive UX, and personalization layers that make your product stand out. Whether you're a startup or scaling a SaaS product, having an expert in AI-native mobile development on your side is a real advantage. 🚀 MVP & Product Launch - My Specialty I've built MVPs from zero to App Store as an android developer and iOS expert more times than I can count. My process: - Clear milestones and rapid iterations for faster time to market - Secure authentication and scalable user management - UX/UI that converts and retains, I've won Dribbble Awards for this - Post-launch support so your product keeps evolving Clients come to me as a trusted full stack developer partner - not just a coder-for-hire. I've helped businesses double their GPM and achieve at least 42% ROI on their mobile investment. ⚙️ Who I Work With I'm a great fit if you're building: - A React Native cross-platform app for iOS & Android - A SaaS mobile product with a Node.js or Firebase backend - An AI-powered mobile experience -A wellness or health app (deep niche experience) - A web application alongside your mobile product as a web developer who understands mobile-first thinking If you've been evaluating a flutter developer or a full stack developer who can own your entire product lifecycle, I'd love to learn more about your project. I also regularly consult on architecture decisions for teams choosing between React Native, Flutter, and native (kotlin / swift), so even if your stack isn't finalized, that's a great starting point for a conversation. 🛠️ A Note on Stack Flexibility Over 10+ years as a mobile app developer and web developer, I've worked alongside teams using PHP/Laravel backends, and I understand how to build seamless API layers that connect any backend to a React Native frontend. If your existing backend is built on Laravel, Python, or another stack, that's not a blocker; it's just an integration challenge. 📱 Core Expertise ✔️ React Native & Expo - cross-platform mobile app developer ✔️ Full Stack Developer - Node.js, AWS, Firebase, Supabase ✔️ Web Developer & React Developer - Next.js, REST & GraphQL APIs ✔️ Flutter & React Native comparison consulting ✔️ AI app development - LLM integrations and smart UX ✔️ SaaS MVP launch - from wireframe to 100K users ✔️ App Store & Google Play deployment - 32 apps shipped Let's build something that matters. Drop me a message and tell me what you're working on. I'll give you my honest take within 24 hours. Key Words: Flutter Developer | Android Developer | React Native Developer | Nextjs Developer | React Developer | Web App Development | Python Developer | Wordpress Developer | iOS Developer | Android Developer

I am a software engineer with 10 years of experience in software development using J2EE and FE technologies. I have a background in building web services, scalable architectures, cloud technologies, and data management. Core experience: • Web Services, Microservices, REST APIs • Agile Scalable Architectures, High Load Systems, Cloud Technologies, Data Management • Java Performance optimization, Bottlenecks, Concurrency and Multithreading • Front-End, Mobile Application and Desktop Development • Agile Development, CI/CD practices, Security Compliance and more Key skills: • Java · Kotlin · Concurrency & Multithreading · JVM & GC tuning • Spring Framework · RESTful API · Security & OAuth 2.0 · SSL · DNS • Micro services · DigitalOcean · AWS · ActiveMQ · Kafka · RabbitMQ • AI, MCP, prompt engineering • MySQL · PostgreSQL · Oracle · MongoDB · Redis · Hibernate · CRUD & POJO • JS/TS · React · Angular · jQuery · Bootstrap · Thymeleaf · Websockets · SPA · Node.js · Vue.js • RCP · OSGi · EMF · Cross-Platform Apps · SWT • Financial Protocols: FIX, FIX 4.2, FIX 5.0, Arrowhead, Swift I’m proactive and self-motivated developer, energetic and driven by engineering challenges which add maximum value to company and users. I will gladly be a part of a professional team that values honesty and good-natured communication

I’m a senior software developer from Portugal with more than 20 years of experience building commercial desktop and mobile applications. I help teams build, stabilize, refactor, and extend products that involve real technical complexity. My work is focused on desktop and mobile software where senior technical judgment matters: Qt/C++ applications, native iOS and Android apps, performance-sensitive features, media and audio/video pipelines, computer vision, hardware integration, OS-level behavior, and long-term maintainability. I have worked on commercial products used by real customers, including projects such as Rocketbook - Document Scanning, Triller - Music Video Social Network, ROVR Radio - Audio Production & Dashboard, Toby - AI Real-Time Audio Translation, iContact - Camera Widget, VideoShop - Video Composition, iGreet - Augmented Reality Greeting Cards, LeanStreamer - Multiple Audio Encoding Streaming Tool, BigRoom - Automated AI Editor, and other desktop and mobile applications that required reliable implementation and careful technical decision-making. Clients usually hire me when they need help with: • building a desktop or mobile product properly from the ground up • refactoring an existing codebase without unnecessary rewrite risk • solving platform-specific issues that are blocking progress or release • implementing complex native features involving camera, audio, video, files, hardware, or OS APIs • improving architecture, maintainability, performance, and stability • adding senior technical depth to an existing team or codebase My core expertise includes Qt/C++, desktop software, native iOS and Android development, software architecture, refactoring, performance optimization, media processing, computer vision, and hardware or platform-level integration. I’m especially well suited for products that already exist and now need to be improved carefully. That may mean stabilizing a codebase, modernizing architecture, solving difficult technical issues, or extending the product in a way that remains clean and maintainable. I care about building the right foundation early, keeping the codebase understandable, and making technical decisions that still make sense in the long run. If your product already exists and needs senior technical help to move forward safely, I’d be glad to discuss it.

I’m a Unity developer working with C#, mainly focused on gameplay systems like abilities, progression, UI, and core game logic. I’ve built features from scratch and also worked inside existing projects, so I’m comfortable both creating systems and improving what’s already there. I’ve worked on multiplayer and system-heavy features, and I care a lot about making things feel smooth, responsive, and easy to iterate on. I also use tools like ChatGPT and Claude to speed up development when it makes sense, while keeping everything clean and properly structured. If you need help building or refining gameplay systems, feel free to reach out.

I am a dedicated Node.js backend developer with strong expertise in designing and implementing scalable, secure, and high-performance web applications. Over the years, I have built and enhanced numerous projects from scratch, applying modern architecture design patterns, optimizing code, and improving performance to meet business goals and user expectations. My core skills revolve around JavaScript, React, Node.js, PHP, and CSS, allowing me to deliver complete end-to-end solutions. Whether it’s building an efficient backend with Node.js or integrating a powerful React frontend, I ensure seamless connectivity and a smooth user experience. 🔑 My Expertise Backend Development with Node.js Proficient in Node.js for building scalable APIs and server-side logic. Skilled in Express.js and modern frameworks for RESTful API and GraphQL development. Optimization of backend performance, code refactoring, and reducing latency. Designing microservices and serverless architectures with AWS Lambda and Docker. Frontend Integration with React & JavaScript Development of user-friendly interfaces with React and JavaScript. Implementing responsive layouts with CSS and best UI/UX practices. Creating reusable React components and connecting them to robust backend APIs. Supporting React Native applications with optimized backend services. Database Design & Management Skilled in SQL and NoSQL databases, ensuring scalability and high availability. Schema design, query optimization, and integration with backend APIs. Experience with MongoDB, PostgreSQL, and Firebase for real-time data processing. Full-stack Capabilities Combining JavaScript, React, PHP, CSS, and Node.js into complete fullstack solutions. Integrating backend services with modern frontends to deliver smooth user flows. Building SaaS platforms, e-commerce solutions, CRM/ERP systems, and custom dashboards. 🏆 What Makes Me Different End-to-End Ownership – I can take your idea from concept to deployment. From designing the Node.js backend to integrating with React frontends, I cover every layer of the stack. Performance & Scalability – I focus on building solutions that are not just functional but also optimized for growth, ensuring low latency and high throughput. Proven Communication & Leadership Skills – I collaborate closely with clients, clearly explain technical solutions, and lead projects within tight deadlines. Continuous Learning – I constantly upgrade my knowledge, especially in blockchain technology, AI-driven development, and cloud-native architectures. 📂 Types of Projects I Work On Custom Backend Development – RESTful APIs, GraphQL endpoints, and high-performance server logic in Node.js. React Web Applications – Clean, modern, and responsive frontends powered by React and JavaScript. SaaS Platforms – Scalable solutions combining Node.js backend with interactive React dashboards. E-commerce Solutions – Fullstack development with JavaScript, PHP, Node.js, and React, including payments and inventory management. Blockchain Integrations – Working with smart contracts, Web3 APIs, and decentralized identity systems. Legacy System Modernization – Migrating outdated platforms into modern JavaScript + React + Node.js stacks. 🛠️ Technical Skills Languages: JavaScript, TypeScript, PHP Frontend: React, React Native, HTML5, CSS3 Backend: Node.js, Express.js, Laravel Databases: MongoDB, PostgreSQL, MySQL, Firebase DevOps: AWS Lambda, Docker, Kubernetes APIs: RESTful, GraphQL, WebSockets Other: Git, Agile Project Management, CI/CD 🌍 Why Clients Choose Me Fullstack Expertise: I bring together JavaScript, React, Node.js, PHP, and CSS into unified, robust systems. Proven Experience: I have successfully delivered projects for fintech, SaaS, blockchain, e-commerce, and enterprise businesses. Client-Centric Approach: I take time to understand your business needs and translate them into scalable technical solutions. On-Time Delivery: Recognized for completing projects under tight deadlines without sacrificing quality. 📞 Let’s Work Together If you are looking for a Node.js backend developer who also has strong skills in React, JavaScript, CSS, and PHP, I’d love to collaborate with you. My focus is always on building solutions that are secure, scalable, and user-friendly. Whether you need a new platform built from scratch, a backend optimized for performance, or a full-stack application that combines powerful APIs with intuitive frontends, I am here to help. Let’s connect and discuss how I can bring your project to life! 🔑 Keywords included often & naturally: Node.js, React, JavaScript, CSS, PHP, backend developer, react, javascript, backend development.