I’m Rajibul Ahsan, a Senior Full Stack Developer and AI Integration Specialist, helping startups and growing businesses build scalable web apps, mobile apps, MVPs, and AI-powered products. I specialize in cross-platform mobile development with Flutter and React Native (iOS & Android), including full App Store and Google Play publishing support. 96 jobs completed | Top Rated | From frontend and backend to databases, cloud infrastructure, and AI integration — I handle the full development lifecycle myself, so you work with one experienced developer instead of coordinating multiple teams. I have hands-on experience building fintech apps, health and wellness apps, ride-sharing apps, AI-powered connection-based apps, and SaaS products - taking ideas from zero to one with clean code architecture and scalable backend systems. Process Overview - Project Discussion I first understand your app idea, target users, required features, design preferences, and business goals. - Planning & Architecture I create a clear development plan, choose the right tech stack (Flutter, React Native, Node.js, Firebase, or Supabase), and structure the app for scalability, security, and future updates. - UI/UX Implementation I build clean, responsive, and user-friendly screens based on your design or wireframe — optimized for both iOS and Android. - Backend & API Integration I connect Firebase, Supabase, custom REST APIs, OpenAI or LLM-based AI features, payment gateways, user authentication, push notifications, real-time chat, in-app purchases, and other required systems. - Testing & Bug Fixing I test the app on different devices, fix issues, improve performance, and make sure the app runs smoothly across iOS and Android. - App Store & Google Play Submission I prepare the final build, handle all store requirements, and support submission to the App Store and Google Play. - Post-Launch Support After launch, I can help with updates, bug fixes, new features, and long-term maintenance. Why clients choose me: ✔ Top Rated on Upwork ✔ 96+ completed projects | $20K+ earned ✔ 0–4 hour response time | Available full-time ✔ Clean code architecture, cross-platform expertise, thorough documentation & App Store submission support Ready to turn your app idea into a real product? Send me a message or invite me to your job post, and we can schedule a 15-minute call to discuss your idea and next steps.

Most applications don’t fail because of bad ideas. They fail because they are not built to scale, maintain performance, or support long-term business growth. I help startups and businesses build scalable SaaS platforms, web applications, APIs, and mobile apps using React.js, Node.js, React Native, AI integrations, and modern cloud infrastructure. With 10+ years of experience in full stack and mobile development, I focus on building production-ready systems that are stable, scalable, secure, and designed for real-world usage. I’ve worked with startups, growing businesses, and enterprise clients to develop systems that support operations, automation, analytics, and customer-facing platforms. Core Expertise ✔ Full Stack Web Development ✔ SaaS Platform Development ✔ React.js & Next.js Applications ✔ Node.js, FastAPI & Scalable Backend Systems ✔ React Native Mobile Applications ✔ REST API & GraphQL Development ✔ Cloud Infrastructure & DevOps ✔ Database Architecture & Optimization ✔ Scalability & Performance Optimization Technologies • React.js & Next.js • Node.js, Express.js & FastAPI • React Native • PostgreSQL, MongoDB, MySQL & Redis • AWS, Docker, Kubernetes & CI/CD • JavaScript & TypeScript • REST APIs & GraphQL What I Deliver ✅ SaaS platforms & subscription-based systems ✅ Business management systems (ERP, CRM, HRM, LMS) ✅ Scalable backend APIs & cloud infrastructure ✅ Cross-platform mobile applications ✅ High-performance web applications built for long-term growth Why Clients Work With Me • 10+ years of real-world development experience • Strong focus on scalability, performance, and maintainability • Business-focused development approach • Clean, production-ready code quality • Reliable communication and consistent delivery • Long-term technical support and ongoing improvements when needed Flexible Availability: I adapt easily to different time zones and project workflows. Whether you need part-time support or full-time development, I ensure smooth collaboration and consistent progress. Ready to work on both long-term and short-term projects. Whether you’re building from scratch, improving an existing system, scaling infrastructure, or integrating AI, I turn technical ideas into reliable, production-grade systems. I help you build MVP’s & Products that are not just functional, but built for real users, real performance, and real growth. Let’s discuss your project and build something designed for long-term growth.

I have 8+ of experience with Mobile app development using Native as well as Hybrid technologies. I am an expert with Flutter/Dart as well as React Native app development and I have developed a vast range of apps using the same. ✅ TOP 10 on Upwork (Top Rated Plus badge) ✅ Seasoned Flutter & React Native developer (8+ years) ✅ 3.5K+ completed hours Hybrid technologies such as : React Native and Flutter/Dart Native technologies for iOS such as Objective-C, Swift, Xcode Native technologies for Android such as Java, Kotlin, Android Studio, JavaSDK Let's get in touch and discuss game changing mobile app solutions

🎁 𝗜𝗳 𝗜 𝗲𝘃𝗲𝗿 𝘀𝗲𝘁 𝘁𝗵𝗲 𝘄𝗿𝗼𝗻𝗴 𝗲𝘅𝗽𝗲𝗰𝘁𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗰𝗮𝗻’𝘁 𝗱𝗲𝗹𝗶𝘃𝗲𝗿, 𝗜 𝗼𝗳𝗳𝗲𝗿 𝗮 𝗳𝘂𝗹𝗹 𝗿𝗲𝗳𝘂𝗻𝗱, 𝗻𝗼 𝗾𝘂𝗲𝘀𝘁𝗶𝗼𝗻𝘀 𝗮𝘀𝗸𝗲𝗱. ⭐ Top-Rated Plus ✅ 80+ jobs completed successfully ✨ Mastered Vibe and custom coding With 7 years of experience, I’ve worked across every stage of a product’s lifecycle. From shaping new ideas, fixing projects that went off track, to scaling systems for large user bases, I bring practical experience and accountability to every engagement. I’m a Mobile & Full-Stack Developer specializing in 𝗙𝗹𝘂𝘁𝘁𝗲𝗿 and 𝗥𝗲𝗮𝗰𝘁 𝗡𝗮𝘁𝗶𝘃𝗲 apps, with strong experience building real products from design to deployment. I work with traditional stacks and emerging 𝗹𝗼𝘄-𝗰𝗼𝗱𝗲/𝗻𝗼-𝗰𝗼𝗱𝗲 𝗽𝗹𝗮𝘁𝗳𝗼𝗿𝗺𝘀 like 𝗥𝗲𝗽𝗹𝗶𝘁, 𝗟𝗼𝘃𝗲𝗮𝗯𝗹𝗲, 𝗦𝘂𝗽𝗮𝗯𝗮𝘀𝗲, 𝗙𝗶𝗿𝗲𝗯𝗮𝘀𝗲, 𝗮𝗻𝗱 𝗕𝗼𝗹𝘁 to accelerate delivery without sacrificing quality. I use Claude (Anthropic's AI) as an active coding partner throughout my development process, pair programming with one of the most capable AI models out there. I help clients: ✅ Take over, maintain, and scale existing applications ✅ Turn Figma designs into functional UI ✅ Build admin dashboards and user interfaces ✅ Integrate backend services (auth, database, APIs) ✅ Ship mobile apps to App Store and Google Play Whether the goal is rapid prototypes, MVPs, or long-term product ownership, I focus on clarity, clean code, and predictable results. Let's have a Call or chat?

🔥 Top Rated Plus on Upwork 🔥 9+ Years of Win Record 🔥 55 Total Jobs Completed 🔥 4200+ Hours Hello, I have been working from the past 9+ years of experience in mobile app development, I have successfully delivered 55+ projects, which have added up to more than 4,267 hours of work and have earned me more than $70K on Upwork. With a Top-Rated badge, I am committed to delivering high-quality, scalable, and user-friendly applications that fit your business needs. 💡 What I Offer: ✅ Cross-Platform Development – React Native & Flutter ✅ Native Mobile Development – iOS (Swift, Objective-C) & Android (Kotlin, Java) ✅ End-to-End App Development - From UI/UX to deployment ✅ Third-Party API Integrations - Firebase, Stripe, Google Maps, REST & GraphQL APIs ✅ App Maintenance & Scaling – Performance optimization & bug fixes 🔥 Why Hire Me? ✔️ Over 8+ years of experience in hands-on development ✔️ Proven track record for 55+ completed projects ✔️ 4,267+ hours worked with a 5-star rating ✔️ Top-Rated freelancer with a strong commitment to deadlines & quality 📩 Let's discuss your project and bring your mobile app ideas to life! ????

SaaS developer & React Native specialist. I build full-stack SaaS platforms and mobile apps for startup founders — from MVP to App Store launch. 146+ projects shipped. 100% Job Success Score. Top Rated Plus. I partner with early-stage founders and growing SaaS companies to design, build, and launch products that work in production — not just in demos. My core stack is React Native, Flutter, Next.js, Node.js, and Supabase, with AI integration (OpenAI, GPT-4, Claude API, LangChain) built in where it creates measurable value. What I build: — Full-stack SaaS platforms with auth, billing, dashboards, and multi-tenant architecture — React Native and Flutter mobile apps for iOS and Android — AI-powered features and agents using OpenAI, GPT-4, Claude API, and LangChain — Supabase and Firebase backends built to scale — MVPs taken from idea validation to App Store and Google Play launch What I bring: — $300K+ in completed Upwork contracts as a Top Rated Plus freelancer — 146+ projects shipped across SaaS, Finance, Healthcare, EdTech, Marketplaces, and AI — 100% Job Success Score across 8+ years of client work — Products used by thousands of users in production worldwide I write clean, well-documented code your next developer can open and build on immediately. I communicate daily, flag risks early, and stay fully invested from kickoff through launch. Stack: React Native · Flutter · Expo · Next.js · Node.js · TypeScript · Supabase · Firebase · PostgreSQL · OpenAI API · Claude API · GPT-4 · GraphQL · REST APIs · AWS · Vercel · GitHub Actions If you're building a SaaS platform, mobile app, startup MVP, or AI-powered product — send me a message and I'll tell you exactly how I'd approach it.

🎯 Top Rated | 100% Job Success | Trusted by global clients React Native & MERN Stack Developer | 10+ Years | 77+ Projects Delivered I have spent the last 10+ years building full-stack web and mobile applications that don’t just work, but scale smoothly as products grow. With 77+ completed projects and a consistent 100% Job Success Score, I focus on delivering systems that are reliable, maintainable, and ready for real users. My core strength sits at the intersection of React Native and the MERN stack, helping founders and teams build connected web and mobile experiences without fragmentation. What I Do: I build complete products end-to-end, from frontend to backend to deployment. ▸ Mobile Apps: React Native apps for iOS and Android with clean architecture and smooth performance ▸ Frontend (Web): React.js, Next.js, responsive UI, dashboards, SaaS platforms ▸ Backend: Node.js, Express.js, REST APIs, authentication, scalable architecture ▸ Database: MongoDB (design, optimization, schema structuring) ▸ Integrations: Third-party APIs, payment systems, real-time features ▸ Deployment: AWS, Vercel, CI/CD pipelines, production-ready setups How I Work ▸ Plan architecture that supports scale from day one ▸ Keep code clean, structured, and easy to extend ▸ Maintain clear communication with regular updates ▸ Work closely with product teams to align tech with business goals ▸ Deliver features that are stable, tested, and production-ready Clients usually come to me when: ▸ They need one developer who can handle both mobile apps and web applications without handoffs ▸ They’re building a product and want a strong foundation for both web and mobile from the start ▸ They need a React Native mobile app connected seamlessly with a web application backend ▸ Their existing mobile or web app needs fixing, scaling, or proper completion ▸ They want clean, maintainable code that’s built for long-term use, not quick patches Experience Snapshot ▸ Web applications with dashboards, user flows, and subscription systems ▸ Mobile apps with real-time features, notifications, and live data ▸ Marketplace and booking platforms across web and mobile ▸ Mobile apps fully connected with scalable backend systems ▸ API-driven products with multiple third-party integrations Approach I start by understanding the product, not just the features. Once the direction is clear, I build with proper structure and clarity, avoiding shortcuts that cause issues later. The focus is always on creating web and mobile applications that run smoothly now and are easy to scale over time. Let’s Talk If you're working on a mobile app, web application, or both, I can help you plan, build, or complete it the right way. Send me a quick message with your idea or current setup, and I’ll take it from there.

I build AI-powered full-stack products - GPT chatbots, React Native mobile apps, and MERN SaaS platforms, used by millions of users worldwide. My apps have reached 𝟭𝟬,𝟬𝟬𝟬,𝟬𝟬𝟬+ active users. 𝗖𝗥𝗘𝗗𝗜𝗕𝗜𝗟𝗜𝗧𝗬 ✔ 𝗧𝗼𝗽 𝗥𝗮𝘁𝗲𝗱 𝗣𝗹𝘂𝘀 - 𝟭𝟬𝟬% Job Success Score on Upwork ✔ $300K+ earned across 59 successfully delivered projects ✔ 𝟵+ 𝘆𝗲𝗮𝗿𝘀 of hands-on experience in web and mobile development ✔ 𝟲𝟬+ 𝗮𝗽𝗽𝘀 shipped across fintech, healthtech, SaaS, AI, education, navigation, e-commerce, and logistics 𝗪𝗛𝗔𝗧 𝗜 𝗕𝗨𝗜𝗟𝗗 - 𝗔𝗜 𝗙𝗜𝗥𝗦𝗧 AI & Automation → GPT- 4 / Claude / Gemini / Anthropic API integration → AI chatbots, smart search, and recommendation engines → LLM-based workflows, agents, and document processing → NLP - sentiment analysis, intent detection, auto-suggestions → Predictive analytics and AI dashboards Mobile App Development → React Native - iOS + Android from one codebase → Flutter cross-platform apps → App Store and Play Store deployment, end to end → Push notifications, offline support, performance optimisation Full-Stack Web & SaaS → React, Next.js, Node.js, Express - scalable MERN architecture → REST and GraphQL APIs built for growth → PostgreSQL, MongoDB, Firebase, MySQL, Firestore → Stripe, PayPal, OAuth, JWT - payments and auth done right → AWS, Vercel, Digital Ocean - CI/CD pipelines and deployment 𝗛𝗢𝗪 𝗜 𝗪𝗢𝗥𝗞 - 𝗣𝗥𝗢𝗖𝗘𝗦𝗦 Every project follows a clear 4 - step process: 𝟭. 𝗗𝗶𝘀𝗰𝗼𝘃𝗲𝗿𝘆 𝗰𝗮𝗹𝗹 - I map your requirements, tech stack, and timeline before writing a single line of code. 𝟮. 𝗦𝗰𝗼𝗽𝗲 𝗱𝗼𝗰𝘂𝗺𝗲𝗻𝘁 - you receive a written plan with milestones, deliverables, and cost. No surprises. 𝟯. 𝗕𝘂𝗶𝗹𝗱 𝘄𝗶𝘁𝗵 𝘄𝗲𝗲𝗸𝗹𝘆 𝗱𝗲𝗺𝗼𝘀 - you see real progress every week, not just a final delivery at the end. 𝟰. 𝗟𝗮𝘂𝗻𝗰𝗵 𝗮𝗻𝗱 𝗵𝗮𝗻𝗱𝗼𝘃𝗲𝗿 - full documentation, deployment, and a 2-week post-launch support window included. 𝗪𝗛𝗬 𝗖𝗟𝗜𝗘𝗡𝗧𝗦 𝗛𝗜𝗥𝗘 𝗠𝗘 ✔ I communicate in plain business language not just technical jargon ✔ Honest timelines - I tell you what's realistic before we start, not after ✔ Clean, well-documented, scalable code you can hand to any developer in the future ✔ I've built for early-stage startups all the way to products with 10M+ users, I adapt to your scale ✔ 100% Job Success Score across 59 projects is the track record, not just a claim 𝗥𝗜𝗦𝗞 𝗥𝗘𝗩𝗘𝗥𝗦𝗔𝗟 Not sure if I'm the right fit? Let's have a free 30-minute discovery call first. I'll review your idea, suggest the best technical approach, and give you an honest estimate, no cost, no obligation. If I'm not the right person for your project, I'll tell you before we start. 𝗖𝗔𝗟𝗟 𝗧𝗢 𝗔𝗖𝗧𝗜𝗢𝗡 Have a project in mind - or just an idea you want to validate? Send me a message or click "𝗜𝗻𝘃𝗶𝘁𝗲 𝘁𝗼 𝗝𝗼𝗯." I reply within 1 hours.

🟢 Available Now • Invite Me to Start Today 🟢 I'm Kailash, a Senior Mobile App Developer specializing in Flutter, React Native, iOS (Swift & SwiftUI), Android (Kotlin & Java), AI-powered mobile applications, Firebase, Supabase, and scalable backend integrations. 🏆 Top Rated Freelancer ⭐ 100% Job Success ⭐ 50+ Successful Mobile Projects ⭐ Thousands of Development Hours Delivered ⭐ Long-Term Client Relationships ⭐ Available for Immediate Start I help startups, founders, agencies, and growing businesses build beautiful, scalable, high-performance mobile applications that users love and businesses can grow with. Whether you're launching a brand-new MVP, modernizing an existing application, adding AI capabilities, scaling to thousands of users, or publishing to both the App Store and Google Play, I take ownership from planning through launch and long-term support. I don't just build apps. I help build successful products. From architecture and UI/UX implementation to backend integrations, cloud services, AI features, testing, deployment, analytics, and maintenance, I work as an extension of your team to ensure your product succeeds long after launch. Why clients hire me: I build once and run everywhere with Flutter and React Native, so a single codebase serves both Android and iOS, which lowers cost and keeps the experience consistent. When a project needs native power, I work directly in Swift for iOS and Kotlin/Java for Android. And I build AI in responsibly, from chat and smart recommendations to OpenAI and LLM features, so the product feels modern without shipping unreviewed output to users. What I do: ✔ Cross-platform development with Flutter and React Native (Expo or bare) ✔ Native iOS (Swift, SwiftUI) and Android (Kotlin, Java) ✔ AI integration: OpenAI, LLMs, chatbots, smart recommendations ✔ APIs (REST, GraphQL), secure auth, real-time data, and offline-first behavior ✔ Push notifications, in-app purchases, and subscriptions (FCM, RevenueCat, Stripe) ✔ Multi-language and Arabic RTL localization ✔ App Store and Google Play publishing, TestFlight, and store optimization I care about what users actually feel: fast load times, smooth navigation, accurate data, and an interface that looks premium on every screen size. I test on real iOS and Android devices, not just simulators, because that is where push notifications, background behavior, and edge cases usually break. A Brand apps I've shipped to the stores: ✅ Silverback (Fintech): secure auth, financial data, subscriptions, both stores ✅ YelsaConnect: real-time features, notifications, user management, both stores ✅ Deal Connect (Real Estate): data-heavy listings, maps, live backend, both stores ✅ Smiling Mind (Healthcare): polished, accessible, engagement-focused experience Why Clients Enjoy Working With Me I believe great communication is just as important as great code. Clients appreciate that I ask thoughtful questions, identify risks before development begins, suggest practical improvements, and keep projects moving with regular updates and transparent timelines. I write clean, maintainable, and scalable code that other developers can easily understand, making future updates faster and more cost-effective. Client Feedback ★★★★★ "Kailash is one of the best mobile developers we've worked with. Excellent communication, strong Flutter expertise, and always delivered high-quality work on time." ★★★★★ "Fantastic React Native developer. He quickly understood our requirements, suggested better technical solutions, and delivered a polished app." ★★★★★ "Very professional, responsive, and proactive. He treated our project like his own and made the entire development process smooth from start to finish." ★★★★★ "Outstanding experience. Clean code, beautiful UI, reliable backend integrations, and successful App Store approval. Highly recommended." ★★★★★ "Excellent Flutter developer with deep mobile knowledge. We'd happily work with him again on future projects." My Development Process Understand your business goals Plan scalable architecture Build clean UI and reliable backend integrations Thorough testing on real devices Performance optimization Security review App Store & Google Play deployment Long-term maintenance and feature enhancements Technologies Flutter • React Native • Dart • JavaScript • TypeScript • Swift • SwiftUI • Kotlin • Java • Firebase • Supabase • AWS • Node.js • Express.js • REST API • GraphQL • MongoDB • PostgreSQL • MySQL • Redis • OpenAI • ChatGPT • GPT-4 • Claude • Gemini • AI Chatbots • AI Assistants • RAG • LangChain • RevenueCat • Stripe • Google Maps • Apple Maps • Push Notifications • FCM • Authentication • Social Login • Deep Linking • Offline Storage • SQLite • App Store • Google Play • TestFlight • CI/CD • GitHub • Git • Agile • Scrum • Mobile UI • Material Design • Cupertino • Cross Platform Development • Enterprise Mobile Apps • SaaS Mobile Apps • Startup MVP Development • App Maintenance

Senior Mobile App Developer | iOS, Android, Flutter & React Native ⭐ Top Rated Plus: Top 3% Talent on Upwork 📱 20M+ active users across apps I’ve built 💯 100% Client Success Score ✅ 80+ successfully delivered projects 🕒 8+ years of mobile app development experience Most businesses struggle with app development because of poor communication, unstable code, delays, and developers who focus only on coding instead of the actual product goals. That’s where I work differently. I help startups, growing businesses, and enterprises build high-performance mobile apps that are scalable, user-friendly, and built for real-world usage, not just app store launches. 💬 𝗪𝗵𝗮𝘁 𝗖𝗹𝗶𝗲𝗻𝘁𝘀 𝗦𝗮𝘆 → “Bhavesh is skilled, trustworthy, dependable, and delivers complex projects with ease.” → “Extremely professional, always on time, and excellent at staying aligned with requirements.” → “Fast, highly skilled, and a true professional. Highly recommended.” ✅ 𝗪𝗵𝘆 𝗖𝗹𝗶𝗲𝗻𝘁𝘀 𝗣𝗿𝗲𝗳𝗲𝗿 𝗪𝗼𝗿𝗸𝗶𝗻𝗴 𝗪𝗶𝘁𝗵 𝗠𝗲 ▸ Business-focused app development ▸ End-to-end delivery, UI/UX, development, backend & deployment ▸ Native + cross-platform expertise (Flutter, Swift, Kotlin) ▸ Scalable architecture with clean, maintainable code ▸ Clear communication & reliable timelines ▸ Long-term technical partnership mindset 📱 𝗠𝗼𝗯𝗶𝗹𝗲 𝗔𝗽𝗽 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 𝗘𝘅𝗽𝗲𝗿𝘁𝗶𝘀𝗲 Flutter & Cross-Platform Development ▸ Flutter & Dart ▸ Firebase & Supabase ▸ Cross-platform iOS & Android apps ▸ Real-time apps & API integrations Native iOS Development ▸ Swift, SwiftUI, UIKit, Objective-C ▸ iPhone & iPad app development ▸ App Store deployment Native Android Development ▸ Kotlin, Java, Android SDK ▸ Jetpack components ▸ Play Store deployment AI-Powered Mobile Apps ▸ OpenAI / GPT integration ▸ AI chatbots & automation ▸ Machine learning & AI features Backend & Full-Stack Solutions ▸ Node.js, Express.js, Firebase, Laravel ▸ MongoDB, MySQL, PostgreSQL ▸ REST APIs & cloud integrations 📌 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝗶𝗲𝘀 & 𝗔𝗽𝗽𝘀 𝗜’𝘃𝗲 𝗕𝘂𝗶𝗹𝘁 ▸ Startup MVP mobile apps ▸ AI-powered applications ▸ Health & fitness apps ▸ Dating & social networking apps ▸ Food delivery apps ▸ Travel & booking platforms ▸ Chat & real-time messaging apps ▸ Audio/video calling apps ▸ Finance & fintech apps ▸ E-learning & EdTech platforms ▸ Marketplace & eCommerce apps ▸ Productivity & SaaS tools 📩 Let’s Build Your App Whether you’re validating an MVP, scaling an existing app, or building an enterprise mobile platform, I can help you design, develop, and launch a reliable mobile product. Send me an invite and let’s build a mobile app that aligns perfectly with your vision. 📌 Keywords to Find Me Mobile App Developer, Flutter Developer, Flutter App Development, iOS App Developer, Android App Developer, Native Mobile App Development, Cross-Platform Mobile Developer, AI Mobile App Developer, Full Stack Mobile App Developer, Firebase Developer, Swift Developer, Kotlin Developer, React Native Developer, MVP App Development, Chat App Development, Dating App Development, Food Delivery App Development 12 may