Jianlong N.

I help startups and businesses build, launch, and scale high-quality mobile applications for iOS and Android. With 15+ years of mobile development experience and 10+ years specializing in React Native, I've delivered production applications used by hundreds of thousands of users and generated over $500,000 on Upwork through long-term client partnerships. Whether you need to build a new product from scratch, improve an existing application, or solve difficult technical issues, I can take ownership of the entire mobile development lifecycle. What I can help you with ✅ React Native & Expo Development ✅ Cross-platform iOS & Android Apps ✅ MVP Development for Startups ✅ AI-powered Mobile Apps (OpenAI, Claude, Gemini) ✅ Firebase & Supabase Integration ✅ Push Notifications ✅ In-App Purchases & RevenueCat ✅ Stripe Payments ✅ Authentication & Social Login ✅ Maps, GPS & Location ✅ Camera, QR Code & Media Processing ✅ Chat & Real-time Messaging ✅ Performance Optimization ✅ Crash Investigation & Bug Fixing ✅ App Store & Google Play Release My experience Before freelancing, I worked as a Senior Mobile Engineer at Haier (Fortune Global 500), where I participated in developing and maintaining more than 100 mobile applications, including products with over one million users. Later, I joined a US startup as the lead React Native engineer and built the company's cross-platform mobile application from scratch. I was responsible for architecture, feature development, payment systems, live streaming, creator features, app performance optimization, and long-term product maintenance. Today, I primarily work with startups and established companies to build reliable, scalable mobile products that are ready for production. Why clients work with me ✔ 500K+ earned on Upwork ✔ 10,000+ development hours ✔ Long-term client relationships ✔ Clean, maintainable code ✔ Excellent communication ✔ Fast response time ✔ Strong debugging and performance optimization skills ✔ Able to work independently with minimal supervision If you're looking for someone who can build, improve, or maintain a production-ready mobile application—not just write code—I'd be happy to discuss your project. Let's build something great together.