Denys S.

Hello and welcome! I am a React Native Developer and Kotlin Developer with more than 7 years of reliable development and custom approaches to my clients, building mobile applications for Android and iOS. My main focus is developing reliable React Native mobile apps and native Android applications using Kotlin. I work on both new mobile products and existing apps that need improvements, refactoring, or performance optimization. Many companies choose React Native to build cross platform mobile applications faster while keeping a high quality user experience. I help teams build scalable React Native apps, integrate APIs, and maintain clean codebases that can grow with the product. When a project requires deeper platform control or Android specific features, I build native Android apps with Kotlin, focusing on performance, stability, and long term maintainability. I usually work with startups and companies that need an experienced mobile developer who can take responsibility for the mobile side of the product and deliver production ready applications. Mobile Development Expertise React Native Developer Kotlin Developer Mobile App Developer Android App Development Cross Platform Mobile Development Mobile App Architecture Mobile App Performance Optimization Mobile App Development Services React Native mobile app development Cross platform apps for iOS and Android Native Android development with Kotlin Improving and maintaining existing React Native apps Refactoring legacy mobile codebases REST API and backend integration Firebase integration and backend services Push notifications and real time features Payments and subscriptions Maps and geolocation features Mobile app performance optimization Bug fixing and long term maintenance Google Play and App Store release support Tech Stack React Native Kotlin Firebase Supabase REST API Android Studio Xcode GitHub CI/CD tools Programming Languages JavaScript TypeScript Kotlin Swift Platforms Android iOS Tablets Databases Firebase PostgreSQL SQLite Redis I build stable and scalable React Native apps and Kotlin Android apps that are ready for production and real users. If you need a React Native developer or Kotlin Android developer to build or improve a mobile app for Android or iOS, I can help deliver a reliable solution.