SANJAY SINGH B.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

Mobile Apps Expert | 10+ Years of Experience Android • iOS • Flutter • React Native • Kotlin Multiplatform • AI Agentic Tools • Cloud Apps I’m a Senior Mobile Developer with 10+ years of experience delivering fast, stable, and scalable mobile applications for startups, enterprises, and global brands. I specialize in building high-quality Android, iOS, and Cross-Platform apps using Flutter, RN, and KMP, all with clean architecture and production-ready code. 💡 Whether you need a new app, want to fix or optimize an existing one, or plan to scale with cloud + AI-powered features, I can help you deliver a polished product—on time and with zero hassle. 📱 Mobile App Expertise 🔹 Android SDK/NDK – Deep hands-on experience with Java, Kotlin and Compose 🍎 iOS Development – Expert in Objective-C, Swift and Swift UI 🧩 Cross-Platform Mastery – Flutter, React Native, and Kotlin Multiplatform (KMP) 🧱 Focus on performance, scalability, and native-like UX across platforms 🧠 Architecture & Code Quality 🧭 Strong in MVP, MVVM, MVI and Clean Architecture 🧩 Experienced in modular app design, ensuring scalability & maintainability 🧹 Advocates clean code, SOLID principles, and test-driven development (TDD) 🌐 Real-Time & Networking ⚡ Built real-time apps using Socket Programming and XMPP (chat, live updates) 🔗 Expert in REST, GraphQL, Retrofit, and RxJava for API integration 🗄️ Database & Data Handling 💾 Proficient in SQL (MySQL, PostgreSQL) and NoSQL (MongoDB, Firestore, CouchDB) 🧮 Skilled in data modeling, indexing, and query optimization for performance 🔌 Integrations & SDKs 🌍 Integrated Google APIs (Maps, Location, Directions, Calendar) & Facebook SDK/Graph API 🔥 Experienced with Firebase Suite – Auth, Firestore, Notifications, Crashlytics, Analytics 💳 Implemented multiple payment gateways – Stripe, PayPal, Braintree, Razorpay 📊 Used PubNub, ElasticSearch, and analytics tools for live data tracking 🧰 Version Control & CI/CD 🧠 Strong with Git, GitHub, GitLab, and Bitbucket ⚙️ Automated builds & deployments via Jenkins, GitHub Actions, Bitrise, Fastlane 🪙 Blockchain & Emerging Tech 🔗 Hands-on with Corda, Hyperledger Fabric/Indy 🌐 Exposure to Web3, NFTs, and Solidity Smart Contracts for Apps 🤖 AI-Accelerated App Development (Agentic AI Tools) ⚡ Faster, Smarter Development – Harnessing Agentic AI tools like Qoder, Gemini, Claude, and OpenAI Coder to accelerate app delivery. 🧠 AI-Assisted Architecture & Coding – Designing scalable architectures and generating clean, maintainable code through AI-driven suggestions. 🧩 Context-Aware Coding Agents – Utilizing autonomous AI agents that refactor code, suggest optimizations, and enhance quality in real time. 🔄 Rapid Prototyping & Iteration – Turning ideas into functional prototypes faster with AI-driven UI generation and auto-code completion. 🧮 Smart Debugging & QA – Detecting bugs and writing test cases automatically using AI-assisted workflows. 💬 Natural Language Development – Writing and reviewing code through conversational prompts using Claude, Gemini, or OpenAI Coders. 🚀 Productivity Multiplied – Delivering production-ready apps faster, with higher quality and efficiency through AI + human expertise. 🎨 UI/UX & Collaboration 🎯 Worked closely with designers using Figma, Adobe XD, Sketch ✨ Built responsive UIs, custom animations, and smooth navigation flows 🤝 Soft Skills & Leadership 🧩 Excellent communicator & agile team player 🧑‍💻 Strong in client communication, requirement gathering, and scrum process 🧭 Proven leader – mentoring juniors & delivering complex apps on time