Ranjeet Singh S.

I’m a Mobile App Developer specialising in React Native, Flutter, iOS, Android, and AI-powered mobile applications. With 186+ completed jobs and 14,000+ hours on Upwork, I help startups and businesses build, launch, improve, and maintain reliable mobile apps. Whether you need a new mobile MVP, an existing app fixed, an AI feature integrated, or a production application taken to the next level, I can help turn your requirements into a practical, working solution. I develop cross-platform and native mobile applications with a focus on usability, performance, maintainability, and reliable releases. My core areas include: - React Native and TypeScript - Flutter and Dart - Native iOS development using Swift - Native Android development using Kotlin - Cross-platform iOS and Android applications - Mobile app MVPs and startup products - Existing app maintenance, debugging, and feature development - API integration, authentication, and backend connectivity - Firebase, push notifications, and real-time functionality - App testing, performance optimisation, and App Store / Google Play releases AI INTEGRATION FOR MOBILE AND WEB APPS I also work on integrating AI capabilities into applications, helping businesses introduce useful intelligence without unnecessarily complicating their products. Relevant technologies and use cases include: - OpenAI APIs and LLM integrations - ChatGPT-powered chatbots and AI assistants - Claude and Gemini integrations - Retrieval-Augmented Generation (RAG) and AI-powered search - Natural Language Processing (NLP) - OCR and document-processing workflows - AI-powered automation and intelligent application features - Python-based AI services and API integrations The right approach depends on your product, data, performance requirements, and budget. I focus on practical integrations that work reliably within the existing application architecture. EXISTING APP IMPROVEMENTS AND PRODUCTION SUPPORT Not every project needs to start from scratch. I can also help with: - Taking over an existing React Native or Flutter codebase - Resolving crashes, bugs, and performance issues - Integrating third-party SDKs and REST APIs - Implementing subscriptions, payments, and notifications where required - Improving application stability and user experience - Preparing applications for testing, release, and ongoing maintenance HOW I CAN HELP I work with startups, growing businesses, and established teams that need a developer who can understand their requirements, communicate clearly, and deliver working software—not just screens or prototypes. My approach is straightforward: understand the problem, recommend a suitable technical solution, deliver in manageable stages, and test the result carefully. If you need a React Native developer, Flutter developer, iOS or Android developer, or support integrating AI into an existing application, let's discuss your project and the best way to move it forward.