Nakul S.

I am a Senior Full-Stack Mobile App Developer with over 10 years of experience architecting high-performance mobile and web ecosystems using React Native, SwiftUI, and Ruby on Rails (ROR). Beyond my technical expertise, I bring a strategic business mindset to every project, having successfully served as a CTO for a venture-funded startup. I specialize in what many consider the industry gold standard for rapid scaling: a robust Ruby on Rails backend combined with intuitive React Native and native SwiftUI frontends. This architecture guarantees a highly secure API backbone alongside a seamless cross-platform or native user experience. Whether you need a high-scale SaaS platform or a native iOS and Android solution, I effectively bridge the gap between complex backend engineering and clean interface design. Why Choose Me as Your Full-Stack Mobile App Developer? * End-to-End Delivery: I manage the full software lifecycle from Ruby on Rails API architecture and database design to App Store and Google Play deployment. * Proven Engineering Leadership: Over 3 years of direct experience managing development teams and scaling codebases for global markets. * Performance-First Mindset: Deep knowledge of Apple Human Interface Guidelines, Google Material Design, and advanced database query optimization. Industry Expertise * On-Demand and Delivery: Two-sided marketplaces, mobile e-commerce apps, and real-time geo-location mapping services. * FinTech and SaaS: Enterprise CRM mobile extensions, payment processing engines, and secure identity verification. * Social and Communication: Real-time chat platforms using WebRTC or Rails Action Cable, social feeds, and smart AI chatbot integration. Technical Stack and Integrations Full-Stack and Mobile Frameworks * Mobile Development: Expert in React Native (Expo), Capacitor, and Ionic for highly responsive cross-platform applications. * Backend Engineering: Specialized in Ruby on Rails (ROR), building scalable MVC frameworks, Sidekiq background processing, and secure REST or GraphQL APIs. * Native iOS and Android: Advanced SwiftUI, Swift, and Kotlin or Jetpack Compose for hardware-intensive mobile requirements. * Core Languages: Full professional proficiency in Ruby, TypeScript, and JavaScript. Specialized Mobile and Web Features * Real-Time and IoT: Seamless server connectivity via Action Cable, WebSockets, and BLE (Bluetooth Low Energy) hardware communication. * AI Integration: Implementation of AI-native app features, large language model (LLM) chatbots, and on-device edge AI. * Health and Fitness: Native device synchronization with Apple HealthKit and Google Fit APIs. Backend, Cloud, and Database Management * Cloud Infrastructure: Expert setup and deployment on AWS (EC2, S3, Lambda), Heroku, and Google Cloud Platform. * Production Databases: Robust, optimized data management using PostgreSQL, Redis caching, and Realm. * API Architecture: Designing mobile-first, low-latency APIs that enforce strict data security. Global Payment and Security Compliance * FinTech and Payments: Secure, localized integration of Stripe Connect, PayPal, Square, and global payment gateways. * Identity and Compliance: Verified regional integration with enterprise compliance frameworks like ELM, Yakeen, WASL, and CITC. * Biometrics: Native execution of FaceID, TouchID, and behavioral mobile biometrics. Quality, Analytics, and DevOps * Product Insights: Event-driven user behavior tracking via Mixpanel, GA4, and AppsFlyer. * CI/CD Pipelines: Automated deployment tracks using GitHub Actions and Bitrise, supported by testing suites via RSpec, XCTest, and Jest. Core Value Add * Architectural Scalability: I write Ruby on Rails backend systems designed to handle millions of requests without breaking. * Rapid Prototyping: Seamlessly combining React Native and ROR to move your concept from an initial MVP to a market-ready product in record time. * Security-First Standard: Integrating encrypted local data storage, OAuth, and strict JWT authentication protocols into every application layout by default Let's Build a Scalable Product Together I do not just write code - I build reliable mobile products that grow with your business. My portfolio below highlights live, production-grade applications utilizing React Native and Ruby on Rails. I am happy to jump on a free 10-minute consultation call to review your mobile app project requirements, evaluate your budget, and choose the most efficient tech stack for your timeline. Click Invite or Hire to get started on your project today.