Denys H.
iOS Engineer iOS App Developer Mobile App Developer iPad watchOS iOS
Senior Mobile Lead Engineer | Claude Code | 10 years of experience | High-quality Mobile and Web Apps Building the Next Generation of Mobile Applications 📊 My Core expertise is the Apple ecosystem, delivering robust solutions across iOS (Swift, SwiftUI), iPadOS, watchOS, and macOS. I work extensively with Swift, SwiftUI, UIKit, Combine, Objective-C, and advanced Apple frameworks such as HealthKit, MapKit, and complex third-party integrations. Beyond development, I provide end-to-end product delivery — from idea validation to App Store release. By combining Business Analysis, UI/UX Design, Agile Development, and Quality Assurance, we build future-proof applications that minimize technical debt and reduce long-term maintenance costs. ⸻ Services I can provide: 📱 Native Mobile Development (iOS & Android) • iOS Development: Swift, SwiftUI, UIKit, Combine, Objective-C • Android Development: Kotlin, Java • Cross-platform: React Native, Flutter • Apple Watch apps, smartwatch apps • Health & fitness apps, Apple Health, HealthKit • Maps & navigation (MapKit, Google Maps, Mapbox) • Real-time features, sockets, charts & analytics 🌐 Web Development • React, Angular, Next.js • TypeScript, JavaScript • High-performance front-end and responsive UI development 🛠 Backend & DevOps • Node.js, Python, Go, PHP • API development & third-party integrations • Cloud deployment: AWS, Docker, VPS 🎨 UI/UX Design & Product Thinking • Figma, wireframes, prototypes, user flows • Product discovery and idea validation before development 📊 Management & QA • Agile project management • Manual & automated testing • Business analysis & product ownership support ⸻ Fintech Expertise • Crypto applications (BTC, ETH, USDT, TRC20) • Real-time exchange data & socket connections • Charts, analytics, and on-chain operations • Secure authentication & sensitive data handling ⸻ Why Clients Choose Us ✔️ iOS-first team with deep expertise as Swift Mobile Developers ✔️ Reliable long-term partner for scalable product development ✔️ Strong focus on performance, usability, and clean architecture ✔️ Transparent communication and Agile processes ✔️ Full-cycle delivery: design → development → QA → release → support ⸻ Looking for a long-term Swift Mobile Developer instead of a one-off coder? If you need a stable, scalable, and carefully crafted mobile product built with modern iOS technologies, let's discuss your goals. I can provide a clear project plan, timeline, budget estimate, and technical strategy tailored to your vision. ⸻ 📩 Send me a message, and I'll share my Upwork scheduler link so we can find a time that works best for you ⸻ 🔑 Technologies & Keywords (SEO Optimized) Swift Mobile Developer, Senior Swift Developer, iOS Developer, SwiftUI, UIKit, Combine, Objective-C, Apple Developer, iPhone App Development, iPad App, macOS App, watchOS App, HealthKit, Apple Health, MapKit, Google Maps, Mapbox, Kotlin, Android Developer, React Native, Flutter, TypeScript, JavaScript, Figma, UI/UX Design, MVP Development, High-Quality App Development, Mobile Architecture, Performance Optimization, Scalable Mobile Apps, Crypto Wallet App, Bitcoin, USDT, tokens, Quality, high-quality app, iPad Developer, iPad Engineer, WatchOS Developer, iOS Developer, iOS Engineer, tvOS Developer
Earnings and projects
Last 6 months ÷ 6
Last 6 months: $99
Billed in all: $74,110$74k
$49 in the last 6 months
Across 43 contracts
Earnings, last 30 days
Skill rankings: Top 30% in Android SDK
Ranked by MRR among everyone on Upwork with the skill.
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