Top Rated Flutter developer based in London. I build AI-powered iOS and
Android apps from first commit to App Store approval. 13 projects
delivered on Upwork with 10 client reviews and a Top Rated badge.
Most clients come to me with one of three problems:
- "We have an AI idea and no mobile app." I build the Flutter app around
it chat interfaces, streaming responses, image/audio input, API
integration with OpenAI, Gemini, or your own model endpoint.
- "Our app works but it's slow, unstable, or stuck in review." I diagnose
it, fix it, and get it shipped. I've rescued codebases I didn't write.
- "We need this built properly the first time." Clean architecture, real
state management, and code your next developer won't curse at.
TECH STACK
Flutter, Dart • Firebase (Auth, Firestore, Storage, Realtime DB, Cloud
Functions) • AI/LLM API integration • REST & GraphQL APIs • Riverpod,
Bloc, Provider • Google Maps & geolocation • Stripe & payment gateways
- Push notifications • Native Swift & Kotlin • App Store and Play Store
submission
HOW I WORK
You get a written plan before I start, working builds you can install and
test as I go, and a reply within a few hours during UK business hours.
I'm in London (UTC+1), which overlaps the US East Coast morning and all
of Europe.
I currently have capacity for one new project.
Send me a message with what you're building and I'll tell you honestly
whether I'm the right fit and roughly what it should cost.
Oleg R.
Flutter Mobile App Development | Android iOS | AI Mobile App Developer
London, United Kingdom
$40/hr$40 per hour4.8 (44) 82 jobs $300K+ total earnings
Full stack mobile app developer with 15+ years of experience in Mobile App Development, specializing in Flutter, React Native, React, IOS, Swift, Android, Python, and Java.
I have successfully delivered 120+ mobile applications in different roles as flutter app developer, flutter full stack developer, flutter flow, ai mobile app developer, mobile app design, mobile ui ux designer, ios developer, android developer, react native developer, mobile game developer achieving a 5-star rating on Upwork and helping clients scale their businesses with high-performance solutions.
🚀 Flutter Mobile App Developer | Mobile UI/UX Designer | Mobile Game Developer | Mobile Web Developer for Mobile app development project.
Expert in Flutter mobile app development, delivering 30+ high-performance apps with pixel-perfect UI and smooth animations. Skilled in clean architecture and comprehensive testing for robust solutions. Experienced Mobile App Developer.
🔹 Applied game mechanics for engaging experiences in mobile development where I was a Mobile Game Developer.
🔹 Integrated real-time features, secure authentication, and cloud functions as Flutter Firebase Developer.
🔹 Built seamless API integrations and data synchronization in mobile development in Flutter mobile app development as a Flutter Laravel Specialist.
🚀 iOS app developer | Mobile UI/UX Designer | Mobile Game Developer | Mobile Web Developer in mobile app development:
Developed and optimized 40+ iOS apps using Swift. Implemented complex features as iOS app developer, maintaining clean architecture and best practices. Leveraged extensive experience as iOS developer Swift to create intuitive user experiences and solve challenging technical problems. Collaborated with cross-functional teams as Swift iOS developer, utilizing Kotlin Swift expertise to deliver high-quality applications on time and exceed client expectations on iOS Swift smartphone platforms.
🚀 Android Developer | Mobile UI/UX Designer | Mobile Game Developer | Mobile Web Developer in mobile app development:
Built 30+ Android apps with adaptive UI, material design, and battery-friendly performance. Expert in Android Kotlin developer, leveraging Kotlin Swift and Kotlin Multiplatform for cross-platform solutions. Optimized security as Android reverse engineer and streamlined releases as Android app publisher, enhancing engagement and update efficiency.
🚀React Native Developer | Mobile UI/UX Designer | Mobile Game Developer | Mobile Web Developer in mobile app development:
Built 20+ cross-platform apps with responsive UI and seamless sync. Expert in React Native mobile, React Native Expo, and React Native Firebase for real-time features. Optimized communication with React Native WebRTC. Crafted interactive experiences as React JS and Front End React specialist. Developed hybrid solutions as Java React expert, maximizing code reuse.
📱 Performance & Scalability: Built apps supporting 1M+ users, integrating real-time updates, gamification, and video streaming.
💰 Business Impact: Helped startups and enterprises generate $10M+ in revenue through well-optimized and engaging mobile applications.
iOS App Development Case Study 📱
Developed a high-performance iOS app using iOS Swift that achieved 5 star rating and featured status in the App Store. Implemented Flutter iOS compatibility for future cross-platform expansion while maintaining native performance and security. Supported iOS app marketing efforts with analytics implementation and App Store optimization, resulting in 35% higher user retention than industry average.
I am currently not accepting WordPress projects as I'm focusing exclusively on mobile app development.
Professional Achievements
🚀 Rewarded as 🏆 𝗧𝗢𝗣 𝗥𝗔𝗧𝗘𝗗 𝗣𝗟𝗨𝗦 🏆
🚀 4154 mobile app development hours on Upwork and still counting
🚀 100% Job Success in mobile app development (Client Satisfaction Ratio)
🚀 54+ mobile app development jobs completed successfully
✅ 98% of Clients Recommended working with me as with AI Mobile App Developer
✅ 80% Long-term Repeat Clients
✅ 15+ Years Of Experience in mobile app development, 6 years experience in Flutter mobile app development, 7 years experience in Swift and Kotlin, 4 years experience in React Native.
✅ High-Quality Work
✅ Cost-Effective AI Mobile App Developer
✅ Fluent English Verified
✅ 93% on-time delivery rate across all mobile app development milestones
Got an app idea that you think is ready to make a splash? Let's dive in and explore it together in a free intro call
I have dedicated over 6 years to professional mobile app development, with a diverse skill set covering iOS, Android, Flutter native, and hybrid app development. During this extensive period, I have successfully crafted more than 25+ apps for clients and companies situated in the UK, USA, Germany, India, and Canada. My clientele ranges from scale-up ventures to Fortune 30+ enterprises.
Here's what I bring to the table:
✅ Proficiency in Flutter and Dart.
✅ Expertise in iOS, Android, Swift, Objective-C, Java, and Kotlin.
✅ Capabilities in client/server development and database/web interfaces.
✅ Firebase, Firestore, Crashlytics, Analytics, Dynamic Links, Cloud Messaging
✅ A keen eye for UI/UX design.
My knowledge of state management solutions such as Provider, Riverpod, GetX, MVC pattern, and Bloc, along with experience in working with different architectures like MVC and MVVM, has allowed me to create robust and efficient applications. I have also integrated various payment gateways like Paypal, Stripe, Rozarpay, and in-app purchases, ensuring seamless payment experiences for users.
Should you be concerned about time-sensitive seasonal updates or feature enhancements, rest assured that I've got you covered. I prioritize building enduring partnerships with my clients, eliminating the need for you to engage multiple developers for each modification or outdated library.
I'm eager to transform your concepts into reality, so please don't hesitate to get in touch and discuss your requirements.
Need a mobile app that is fast, stable, easy to use, and ready for real users on iOS and Android?
I’m a Mobile App Developer specializing in Flutter, React Native, iOS development, Android development, Swift, Java, Kotlin, APIs, Firebase, and scalable mobile application development.
I build mobile apps for startups, SaaS companies, ecommerce businesses, marketplaces, healthcare platforms, booking systems, fintech products, and growing businesses. Whether you need a new mobile app, an MVP, an existing app improved, or a web platform converted into a mobile experience, I can handle the development from architecture through App Store and Google Play deployment.
Mobile App Development
I build complete iOS and Android applications with a strong focus on performance, maintainable code, responsive interfaces, API integrations, and reliable production releases.
✔ Mobile App Development
✔ iOS App Development
✔ Android App Development
✔ Cross-Platform App Development
✔ Mobile MVP Development
✔ SaaS Mobile Applications
✔ Business Mobile Apps
✔ Existing App Improvements
✔ App Bug Fixing
✔ App Performance Optimization
✔ App Store Deployment
✔ Google Play Deployment
Flutter App Development
I develop cross-platform mobile applications using Flutter and Dart for businesses that need a consistent iOS and Android experience from one maintainable codebase.
✔ Flutter Development
✔ Dart Development
✔ Flutter iOS & Android Apps
✔ Flutter Firebase Integration
✔ Flutter API Integration
✔ Flutter UI Development
✔ Flutter App Redesign
✔ Flutter Bug Fixing
✔ Flutter Performance Optimization
✔ Existing Flutter App Development
React Native Development
I build and improve React Native applications using JavaScript and TypeScript for startups, SaaS products, ecommerce platforms, and API-driven mobile applications.
✔ React Native Development
✔ React Native iOS Apps
✔ React Native Android Apps
✔ JavaScript & TypeScript
✔ REST API Integration
✔ Firebase Integration
✔ Authentication
✔ Push Notifications
✔ Payment Integrations
✔ Existing React Native App Improvements
Native iOS & Android Development
For projects that require native functionality, I work with Swift for iOS and Java/Kotlin for Android development.
✔ Swift Development
✔ Native iOS Development
✔ Java Android Development
✔ Kotlin Development
✔ Native Android Development
✔ iOS & Android SDK Integration
✔ Device Features & Permissions
✔ Camera, Location & Maps
✔ Push Notifications
✔ In-App Purchases
✔ App Store & Play Store Releases
Backend, APIs & Mobile Integrations
I connect mobile applications with reliable backend services, databases, payment platforms, authentication systems, and third-party APIs.
✔ REST API Integration
✔ Firebase
✔ Supabase
✔ Node.js APIs
✔ Authentication & User Management
✔ Stripe & Payment Integration
✔ Google Maps Integration
✔ Social Login
✔ Push Notifications
✔ Real-Time Data
✔ Third-Party SDK Integration
✔ Analytics & Crash Reporting
Core Technologies
Mobile: Flutter, Dart, React Native, Swift, Java, Kotlin
Frontend: JavaScript, TypeScript, React
Backend & APIs: Node.js, REST APIs, Firebase, Supabase
Databases: Firebase Firestore, PostgreSQL, MySQL, MongoDB
Integrations: Stripe, Google Maps, Apple Sign In, Google Sign In, Push Notifications
Tools & Deployment: Git, GitHub, Xcode, Android Studio, App Store Connect, Google Play Console
Why Clients Hire Me
✔ Flutter & React Native Development
✔ Native iOS & Android Development
✔ Swift, Java & Kotlin Experience
✔ Cross-Platform Mobile App Development
✔ API & Firebase Integration
✔ Existing Mobile App Improvements
✔ Mobile App Bug Fixing & Optimization
✔ App Store & Google Play Deployment
✔ Clean and Maintainable Development
✔ Clear Communication & Reliable Delivery
✔ Full Ownership From Development to Launch
I focus on building mobile applications that are reliable, scalable, responsive, and ready for real users rather than apps that only work well in a demo.
Whether you need a Mobile App Developer, Flutter Developer, React Native Developer, iOS Developer, Android Developer, Swift Developer, or Java Developer, send me your requirements, existing application, or design files.
I’ll review what you need and recommend the most practical development approach.
SEO Keywords: Mobile App Developer, Flutter Developer, React Native Developer, iOS Developer, Android Developer, Mobile Application Developer, Flutter App Developer, React Native App Developer, Swift Developer, Java Developer, Kotlin Developer, iOS App Development, Android App Development, Cross Platform App Developer, Mobile App Development, Flutter Development, React Native Development, Firebase Developer, Dart Developer, Mobile MVP Developer, App Developer, App Store Deployment, Google Play Deployment, REST API Integration, Firebase Integration
How it works
Post a job for freePost a job
Tell us what you need. Create your own job post or generate one with AI then filter talent matches.
Hire top talent fast
Consult, interview, and hire quickly, so you can meet the freelancers you're excited about.
Collaborate easily
Use Upwork to chat or video call, share files, and track project progress right from the app.
Payment simplified
Manage payments in one place with flexible billing options. Only pay for approved work, hourly or by milestone.
Don't just take our word for it
“Upwork provides an umbrella-level of security. I can see a talent’s work history and ratings. I can hold payments in escrow. I can communicate through Upwork Messages instead of working through my email address.”
KD
Kim Darling
Verified
Emerald Tiger
“Upwork is the best platform to hire skilled professionals when we're not looking for a full-time employee. All the companies in our portfolio use Upwork to find talent across a wide range of fields.”
DM
David Merry
Verified
Kinetic Investments
“Our very specific requirements can be a challenge—With Upwork, we’re able to access a bigger community to ensure the success of our projects.”
KK
Katja Krohn
Verified
Summa Linguae
How do I hire a Flutter Developer in the United Kingdom on Upwork?
You can hire a Flutter Developer in the United Kingdom on Upwork in four simple steps:
Create a job post tailored to your Flutter Developer project scope. We'll walk you through the process step by step.
Browse top Flutter Developer talent on Upwork and invite them to your project.
Once the proposals start flowing in, create a shortlist of top Flutter Developer profiles and interview.
Hire the right Flutter Developer for your project from Upwork, the world's largest work marketplace.
At Upwork, we believe talent staffing should be easy.
How much does it cost to hire a Flutter Developer?
Rates charged by Flutter Developers on Upwork can vary with a number of factors including experience, location, and market conditions. See hourly rates for in-demand skills on Upwork.
Why hire a Flutter Developer in the United Kingdom on Upwork?
As the world's work marketplace, we connect highly-skilled freelance Flutter Developers and businesses and help them build trusted, long-term relationships so they can achieve more together. Let us help you build the dream Flutter Developer team you need to succeed.
Can I hire a Flutter Developer in the United Kingdom within 24 hours on Upwork?
Depending on availability and the quality of your job post, it's entirely possible to sign up for Upwork and receive Flutter Developer proposals within 24 hours of posting a job description.
Find more freelancers
Top cities for Flutter Developers in the United Kingdom