I help teams build stable, high-performance Android applications by making the right architecture decisions early and fixing them when they weren’t. Most Android apps don’t fail because of bad UI. They fail because of fragile architecture and technical debt. I’m a Top Rated Android Engineer with 4+ years of experience delivering production-ready Android apps where performance, stability, and long-term maintainability actually matter. ❖ What I Do I design, build, and maintain native Android applications using proven engineering practices: ✓ Android App Development • Native Android apps with Kotlin & Java • Jetpack, Jetpack Compose, Android SDK ✓ Architecture & Code Quality • MVVM & Clean Architecture (used only when it makes sense) • Refactoring fragile or messy codebases • Reducing long-term technical debt ✓ Performance & Stability • Fixing crashes, ANRs, and memory leaks • Performance profiling and optimization • Production issue debugging ✓ Long-Term App Ownership • Adding complex features safely • Maintaining and scaling existing apps • Taking over apps that need stability and direction ❖ How I Work I don’t start by writing code. Before implementation, I focus on: • Where will this app break in 6 months? • Which parts will be hardest to maintain? • What can be simplified now to save time and money later? Then I design solutions that are: • Predictable to scale • Safe to extend • Easy for other developers to understand I don’t over-engineer. I don’t under-engineer. I engineer for real-world use. ❖ Tools & Technologies ✓ Languages: Kotlin, Java ✓ Android: Android SDK, Jetpack, Jetpack Compose ✓ Async: Coroutines, Flow ✓ Data: Room, Retrofit, Firebase ✓ Media: ExoPlayer ✓ Architecture: MVVM, Clean Architecture ✓ Workflow: Git, Gradle (Strong tools matter — but good decisions matter more.) ❖ Why Clients Hire Me ✓ Top Rated with a proven track record ✓ Strong focus on performance & stability ✓ Honest feedback — even when it’s uncomfortable ✓ Clear communication and realistic expectations ✓ Long-term mindset, not quick fixes If your project is small, I’ll tell you. If something is a bad idea, I’ll tell you. That honesty is why clients rehire me. 🚀 Let’s Work Together I’m not the right fit if you’re looking for the cheapest Android developer. But if you want someone who will think, question, and protect your product, let’s talk. 📩 Send me: • What your app does • What’s currently not working • Where you want it to go I’ll tell you honestly how I’d approach it.

Senior Android Developer with 9+ years building and shipping native Android apps in Kotlin and Jetpack Compose, with 10M+ combined Google Play downloads. I help startups and product teams modernize legacy apps, integrate AI/LLM features, and ship fast, stable, high-performance Android experiences. What I bring to your project: - Native Android in Kotlin, Jetpack Compose, MVVM, Coroutines & Flow, and Hilt - AI integration — on-device ML with TensorFlow Lite, plus OpenAI/LLM API features - Java/XML → Jetpack Compose migrations and full app modernization - Performance tuning (baseline profiles, faster startup), Firebase, REST & GraphQL - CI/CD, automated testing, and clean, maintainable architecture Recent results: - Migrated a legacy Java/XML app to Jetpack Compose (MVVM + Hilt), modernizing the codebase - Built a live-comment feature supporting 1M+ concurrent users - Cut app startup time 15% using Macrobenchmark and baseline profiles - Maintained 100% Job Success and Top Rated status across 46 Upwork jobs I communicate clearly in fluent English, hit deadlines, and care about your users' experience as much as you do. If you need a senior Android engineer to own a feature end-to-end — or rescue a struggling app — let's talk. 📩 Message me first. Tell me about your app, where you are, and what you need. I'll give you a straight answer on what it will take — no sales pitch, no pressure.

A dedicated Software Developer with over twenty years of experience professionally deploying full-cycle solutions. My latest experience is developing complex, market-oriented Android applications, converting Swift code to Kotlin, and troubleshooting bugs in Android applications. With expertise in Android engineering, I will resolve your app development needs while achieving the results expected from a senior professional. I am reliable in working with minimal supervision and always conduct thorough research before reaching out with questions.

Full-Stack AI Apps Developer | Agentic AI & LLM Workflows | Android | iOS | Kotlin Multiplatform | Python | Spring Boot I design and build AI Agent applications, LLM-powered workflows, and full-stack mobile apps end to end. From agent architecture and backend orchestration to native Android, iOS, and cross-platform delivery, I own the entire stack with zero handoff risk. 10+ years of engineering experience, 100% Job Success Score, Top Rated on Upwork. What I Build AI Agent apps and autonomous workflows (Java, Python, Kotlin) · LLM integrations (OpenAI, Claude, Gemini, GPT-4) · MCP (Model Context Protocol) server and client implementations · RAG pipelines with vector database retrieval · AI automation and multi-step agentic workflows · Custom AI assistants and chat apps with streaming responses · Native Android (Kotlin, Jetpack Compose) · Native iOS (Swift, SwiftUI) · Kotlin Multiplatform (KMP) and Compose Multiplatform · Spring Boot backends and microservices powering AI agent apps · E-commerce, healthcare, fintech, and real-time social apps with AI features built in AI & Agent Stack Languages: Java · Python · Kotlin · Swift Agent Frameworks: LangChain · LangChain4j · LangGraph · custom agent orchestration Protocols & Retrieval: MCP (Model Context Protocol) · RAG · Vector Databases (Pinecone, Weaviate, Chroma, pgvector) LLM Providers: OpenAI API · Anthropic Claude API · Google Gemini Workflow & Automation: Multi-agent pipelines, tool-calling agents, autonomous task execution, n8n-style automation logic built natively Backend: Spring Boot · Ktor · REST APIs · WebSockets · JWT Authentication Mobile: Kotlin Multiplatform · Jetpack Compose · SwiftUI · Room · SQLDelight · Firebase Delivered Results AI Agent Assistant App — KMP (Android + iOS) + Spring Boot backend, GPT-4 streaming, tool-calling agent layer, offline voice → 50K+ downloads · 4.7★ · 200K+ AI conversations/month RAG-Powered E-Commerce App — Compose Multiplatform, vector search product recommendations, Stripe, Spring Boot → $2M+ mobile revenue · 99.8% crash-free Healthcare AI Platform — HIPAA-compliant KMP + Spring Boot, AI-assisted triage agent, encrypted offline records → Deployed across 3 hospital networks Real-Time Agent-Driven Social App — WebSocket sync, Spring Boot, automated moderation agent → 10K concurrent users, sub-100ms delivery Why Clients Choose Me ✔ Full-stack ownership — AI agent logic, backend orchestration, mobile UI, deployment, all by one engineer ✔ Deep experience with MCP, RAG, and vector databases, not just prompt wrapping ✔ Production-grade agent workflows in Java and Python, integrated into real mobile and backend systems ✔ 100% Job Success Score · Top Rated on Upwork ✔ Fast, proactive communication and a product-focused approach Send me an invite or message. I'll respond within a few hours with a clear technical approach for your AI agent or mobile project. Muhammad Hassan Full-Stack AI Apps Developer | Agentic AI & LLM Workflows | Android | iOS | Kotlin Multiplatform | Python | Spring Boot

Greetings All, I'm a Lead Architect with 11+ years of experience in web development. I have developed different kinds of projects, including eCommerce systems, CRM software, corporate websites, APIs and other internal scripts. • A quick learner with a penchant of performing under pressure. strong team player with excellent interpersonal and communication skills, strong analytical and problem solving skills. • Overall 11+ years of experience in development of Mobile, Web & Enterprise applications using PHP5, JAVA and J2EE Technologies. • Artificial Intelligence and Automation - Prompt Engineering, AI Agent Development using n8n - Large Language Model Integration and Conversational AI using Langchain and Botpress - AI Chatbots, Retail AI Voice Bots, and Generative AI • Hands on experience in Core Java, Servlets, JSP, JDBC, Spring, SpringBoot, Hibernate, JPA, JavaFX, JacpFX. • Hands on experience with DevOps, Shell Script, Docker, Docker Compose, Jenkins, AKS, Azure • Hands on experience in NodeJS, Angular, Angular 2-rc3, Ionic Framework. • Hands on experience in ReactJs and Redux Frameworks. • Hands on experience in MySQL, Postgres, Oracle, MongoDB, ArangoDB, SQL Server. • Hands on experience in Apache, Weblogic, Glassfish, JBoss/Wildfly and Tomcat web servers. • Hands on experience in Ejabberd, Openfire and Prosody XMPP Chat servers. • Hands on experience in WebRTC. • Knowledge of Eclipse, Intellij Idea, WebStorm tool for the development of java projects & Node/Angular. • Knowledge of Adobe DW, Aptana studio tool, PHPStorm for the development of PHP projects. • Knowledge of Business Process Management Tool jBPM5.3. Let me know about your goals and I will lead your project to success! ;)

I’m a mobile developer with 10+ years of experience, delivering iOS and Android apps for startups and growing businesses. I take full ownership of your mobile product — from UI implementation and backend integration to app release — ensuring stable, scalable, and maintainable applications. Core Expertise: • Native Mobile App Development (iOS & Android) • Cross-Platform Development (Flutter, React Native) • MVP Development for Startups • UI/UX Implementation from Figma • Backend & API Integration (Firebase, REST APIs, WebSockets) • Payment Integration (Stripe, Apple Pay, Google Pay, Checkout) • Push Notifications & Real-Time Features • Location-Based Features (GPS, geofencing, check-ins) • Secure Authentication & User Account Systems • Admin Dashboards & Content Management Tools Mobile App Capabilities: Authentication & User Profiles: • Email/password login, social login, phone verification • Onboarding flows & profile setup UI/UX Development: • Pixel-perfect Figma to app implementation • Clean, modern layouts with transitions and animations • Light & dark mode support Real-Time Features: • WebSockets & real-time data synchronization • Live activity feeds, group updates, notifications • Video streaming with low-latency support Payments & Monetization: • Stripe, Checkout, Apple Pay & Google Pay • Escrow systems • Loyalty & reward programs Location-Based Features: • GPS tracking, geofencing, check-ins • Partner & location listings API & Backend Integration: • Firebase, Supabase • Custom backends with Node.js or Python/FastAPI • Third-party API integration Admin Panels & Dashboards: • Content & menu management • Promotions, analytics & reporting Industries: • Fintech & money transfer • Food ordering & loyalty apps • EdTech & gamified learning • Marketplaces & peer-to-peer resale • Social & community apps • Video security & AI analytics • Health, wellness & fitness apps • Productivity & task management tools Work Approach: • Clear and consistent communication • Milestone-based process • Predictable delivery timelines • End-to-end ownership of mobile development • Long-term maintenance & feature expansion available 💬 Let’s discuss your project — I can deliver a reliable, scalable, cross-platform mobile app from idea to MVP or full product, on time and with high technical quality. Keywords: Flutter Developer, Cross-Platform App, Mobile App, iOS, Android, MVP, SaaS, Figma, Firebase, Supabase, Payment Integration, Real-Time Features, GPS, Admin Dashboard

Are you building an Android app and need a developer who actually delivers clean, production-ready code — not just something that works in a demo? I'm a native Android developer with 4+ years of hands-on experience building apps in Kotlin and Java that are scalable, maintainable, and ready for real users. I specialize in modern Android development — Jetpack Compose, MVVM/Clean Architecture, Firebase, and REST API integration — and I care deeply about writing code that's easy to extend, not just easy to ship. Here's what I bring to your project: ✅ Native Android apps built with Kotlin/Java, Jetpack Compose, and the full Android SDK ✅ Firebase integration — Auth, Firestore, Cloud Functions, Crashlytics, FCM push notifications ✅ REST API consumption with Retrofit, proper error handling, and offline-first architecture ✅ Clean Architecture & MVVM patterns — your codebase stays maintainable as you scale ✅ Google APIs — Maps, Places, Drive ✅ Local data with Room, SQLite, and Realm ✅ Third-party SDK integrations — payments, social auth, analytics, and more ✅ Secure, performant builds with Proguard/R8 and Gradle (Groovy & Kotlin DSL) I've worked on apps across healthcare, fintech, and consumer categories — including real-time messaging systems, POS platforms, and data-heavy mobile experiences. I write code I'm not embarrassed to show, communicate proactively throughout a project, and don't disappear after delivery. If you need someone who treats your app like a product — not just a task — let's talk.

A mobile app developer with 10+ years of experience in building native iOS and Android applications and cross-platform mobile apps with React Native and Flutter. I help startups, founders, and businesses turn ideas into high-quality mobile products that are fast, reliable, and built for real-world use. My work covers everything from MVP development and rapid prototyping to full-featured applications with scalable architecture and long-term growth in mind. With strong knowledge of the complete mobile app development lifecycle, I manage projects from idea validation and UI/UX planning to development, testing, deployment, and post-launch support. ❯❯❯❯ Mobile App Development Solutions I Offer ❮❮❮❮ ◆ Native app development for iOS and Android ◆ Cross-platform app development with React Native and Flutter ◆ MVP development for startups and new product ideas ◆ UI/UX design with clean, modern, user-focused interfaces ◆ Backend development and third-party API integration ◆ AI-powered mobile features such as chat, voice, automation, and recommendations ◆ Real-time chat, notifications, and live data sync ◆ Authentication, payments, subscriptions, and secure data handling ◆ Location-based functionality, maps, and GPS tracking ◆ Testing, debugging, optimization, and performance improvements ◆ App Store and Google Play deployment ◆ Ongoing support, updates, and maintenance ❯❯❯❯ Examples of Mobile Solutions Delivered ❮❮❮❮ ◆ On-demand booking and service apps ◆ AI fitness and health tracking apps ◆ E-commerce mobile apps ◆ Real estate property platforms ◆ Social networking and chat apps ◆ Logistics and delivery tracking apps ◆ EdTech and learning apps ◆ AI chatbot and assistant apps ❯❯❯❯ Core Technologies & Tech Stack ❮❮❮❮ ◆ Mobile ➜ Swift, SwiftUI, Kotlin, Jetpack Compose, Flutter, React Native ◆ Frontend ➜ TypeScript, JavaScript ◆ Backend ➜ Node.js, Express.js, Firebase, Supabase ◆ Database ➜ PostgreSQL, MongoDB, AWS ◆ AI ➜ OpenAI, LangChain, LlamaIndex, Google ML Kit, TensorFlow Lite ◆ Tools ➜ Xcode, Android Studio, Cursor, GitHub Copilot, Replit, Expo, FlutterFlow ◆ Testing & CI/CD ➜ Jest, Detox, XCTest, Fastlane, GitHub Actions, Sentry ◆ Design ➜ Figma, Material 3, Apple HIG If you have a mobile app idea or need to improve an existing product, feel free to reach out. Happy to discuss your requirements and suggest the best approach to build a reliable, high-quality solution.

Dedicated Mobile Software Engineer with a strong background in mobile application development and a focus on delivering efficient, user-friendly, and maintainable solutions. Experienced in working with modern Android frameworks, following best practices, and contributing to all stages of the software development lifecycle. My work covers: • Developing new features and improving existing functionality • Writing unit tests to ensure code reliability • Setting up CI/CD pipelines for automated testing, validation, and build distribution • Conducting code reviews and collaborating closely with stakeholders to refine requirements and deliver solutions that meet business goals Tech stack • Android: Kotlin, Jetpack Compose & XML, Coroutines, Hilt/Dagger 2, multi-module architecture • iOS: Swift, SwiftUI & UIKit • CI/CD: GitHub Actions, Fastlane • Additional tools: Firebase, REST APIs, third-party SDK integrations I thrive in small to mid-sized cross-functional teams that include product managers, QA engineers, developers, and designers. My goal is to keep growing in app architecture, testing, and scalable mobile solutions, while contributing to impactful and long-term projects.

Hello! I am expert Backend Developer with almost 20 years of experience in backend, Android mobile, desktop apps, apps for embedded devices, ERP apps and web development. Proficient in developing applications in wide range of areas, including business applications and database management. Have high attitude expertise in Linux OS management, including building automated servers with set of services/tools for different purposes, virtualization tehcnologies like KVM/libvirt, containerization technologies like LXC, Docker, Kubernetes. What I can do: - Planning and implementing the app’s architecture and features. - Writing apps from the very scratch and further support. - Code Review, Fixing and supporting the apps written by others. - Working with a team of developers or solo. Technical Skills: * Languages and Frameworks: Java (Spring, Quarkus, Dropwizard....), Kotlin, C, C++, Qt, Rust, Go, Python (Django), JavaScript, PHP * Platforms: Backend, Android, Linux (Fedora, RedHat, CentOS, Ubuntu) * Technologies: Docker, Kubernetes, CI/CD, Mobile Development, Docker, KVM, libvirt, IT infrastructure monitoring tools, AWS services, GCP * Database Management: PostgreSQL, SQLite, MySQL.... - I'm open to working with big and small companies and individual clients. - I'm comfortable signing an NDA. - Prefer long-term collaboration. - Ready to work 30-60 hours per week I'm open to various projects and would love to show you my creative side too. My commitment to continuous learning keeps me updated with the latest trends and technologies, allowing me to bring cutting-edge solutions to your projects and better expreince. I am giving high attention to details, ready to resolve complicated and complex challenges, always tend to offer most efficient solution. Thanks for your time Regards Rafael S.