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Hire the best Kotlin Developers in Ukraine

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Clients rate Kotlin developers
Rating is 4.8 out of 5.
4.8/5
based on 510 client reviews
  • $50 hourly
    • 5.0/5
    • (19 jobs)
    I specialize in iOS and Android development but also provide end-to-end app development when needed—in partnership with expert UI/UX designers and backend engineers. • Huma (UK healthtech company, $300M funded) – Led iOS development, architected the SDK, and built complex features for remote patient monitoring. • FuboTV (US streaming service with millions of users) – Developed and optimized video playback on iOS, tvOS, and Chromecast for a seamless streaming experience. 📊 Industry Experience: Healthtech, finance, social networking, communication tools, and more—focusing on security, real-time interactions, intuitive UI, and compliance with HIPAA & GDPR standards. 📩 Need expert iOS/Android development or an end-to-end app solution? Let’s discuss how I can help!
    Featured Skill Kotlin
    SwiftUI
    Tablet
    Firebase
    User Authentication
    User Profile Creation
    QA Engineering
    QA Testing
    UX & UI Design
    iOS Development
    Mobile App Development
    Swift
    Android
    iOS
    Smartphone
  • $40 hourly
    • 4.8/5
    • (12 jobs)
    I’m a passionate developer with 7 years of experience. I’m a full stack developer, but i specialize in the field of mobile systems development. My current work includes machine learning systems on mobile devices and custom navigator applications which include from scratch algorithm development, and I also develop native components for Flutter as well as writing Flutter code. I have an experience of working with small companies as well as governmental clients.
    Featured Skill Kotlin
    Smartphone
    Web Application
    Flutter
    Rust
    React Native
    Firebase Cloud Firestore
    Android
    iOS
    AWS Lambda
    Objective-C
    Swift
    C++
  • $35 hourly
    • 4.9/5
    • (8 jobs)
    Hello✌️ Smartphones & tablets📲, watches⌚️, Bluetooth & WiFi connections📶, streaming 📡 development. Vast Expertise, Rapid Delivery, Mobile Technologies, Front-end Technologies, Back-end Technologies. Need assistance in any of these top areas? Welcome! 1. Deep Expertise in Mobile App Development As a seasoned mobile app developer team with over 50 tech specialists, we bring extensive experience to every stage of your product lifecycle. Whether you're launching an iOS app, an Android app, or a cross-platform solution, we support you from idea validation through to the App Store or direct distribution—ensuring efficient, high-quality mobile app development. 2. Accelerated Time to Market My structured development process allows us to deliver iOS apps and Android apps up to 30–50% faster than average providers. As a results-driven mobile app developer, we prioritize reduced Time to Market—giving your business a competitive advantage in fast-moving digital markets. 3. Expert Mobile Technologies Build an exceptional iOS app or Android app with my dedicated mobile app development team. Each mobile app developer at Natife is highly skilled in technologies like Swift, Kotlin, Java, and Objective-C—ensuring top performance, native responsiveness, and clean architecture. 4. Engaging Front-End Interfaces My team of front-end experts collaborates closely with every mobile app developer to create stunning, interactive UI components. Whether for an iOS app or an Android app, we design with purpose—ensuring user engagement and intuitive navigation. 5. Scalable Back-End Solutions A robust back end is essential to seamless mobile app development. As a Mobile app developer, I integrate secure, scalable server logic for both iOS apps and Android apps, ensuring your product performs under high load and delivers consistent user experiences across all platforms. Mobile App Tech Stack ⚜️ Android app development: Kotlin, Java, Jetpack Compose ⚜️ iOS app development: Swift, Objective-C, RxSwift, SwiftUI ⚜️ Back end: JavaScript/TypeScript, Node.js, GraphQL, REST API, AWS, SQL, Serverless ⚜️ Front end: React, Redux, Vue, MUI, Vuetify Case Highlights from Our Mobile App Developers: 📌 As a Mobile app developer for iOS and Android, I’ve built 10+ health apps used by 500,000+ users worldwide—featuring biometric sensors, HIPAA compliance, and real-time health tracking. 🩺📊 📌 As a Mobile app developer I've built 50+ Native iOS and Android apps. 📌 As a Mobile app developer for iOS and Android, I’ve created fintech and e-commerce apps that processed over $15M annually with 99.98% uptime and PCI DSS-compliant payment systems. 💰📱 📌 As a Mobile app developer for iOS and Android, I developed productivity platforms using AI to automate workflows—helping teams manage over 250,000 tasks and increase retention by 37%. 🧠📅 📌 As a Mobile app developer for iOS and Android, I built logistics and booking apps across 60+ cities, enabling 1M+ successful deliveries and reservations via real-time GPS tracking. 🚗📍 📌 As a Mobile app developer for iOS and Android, I launched IPTV and streaming apps used by 100K+ daily viewers, with playback latency optimized to under 0.8s. 📡🎧 📌 As a Mobile app developer for iOS and Android, I released social and fitness apps with 2M+ downloads, real-time chat, fitness tracking, and viral mechanics that boosted daily active users by 45%. 💬💪 Reach out to us in the Upwork chat📩, and we will discuss all important matters. Regards, Valerii
    Featured Skill Kotlin
    Native App
    Native App Development
    Firebase
    SwiftUI
    Mobile App
    Smartphone
    Smart TV
    Wear OS
    iOS
    Apple Watch
    Android App Development
    Mobile App Development
    Swift
    iOS Development
  • $40 hourly
    • 5.0/5
    • (12 jobs)
    👩‍💻 Hi! I'm Ann - Your Expert Mobile App Developer As a seasoned Mobile App Developer, I specialize in creating high-performance native apps for iOS and Android, using Swift, Kotlin, and Java. My deep knowledge as a Mobile App Developer spans across SwiftUI, Combine, Jetpack Compose, ARKit, and the Android SDK, enabling me to deliver world-class mobile experiences. Throughout my career as a Mobile App Developer, I’ve helped 60+ companies and startups turn their app ideas into full-fledged products. With 7+ years of commercial experience in Mobile App Development, I’ve partnered with 40+ global clients, providing scalable, future-proof mobile solutions. From native iOS to Android, I approach every project as a passionate Mobile App Developer focused on quality, performance, and results. As a Mobile App Developer, I lead a strong, dedicated team of 50 Mobile App Developers — each contributing their expertise to build exceptional mobile applications. We’re proud to be a Top Rated Plus Mobile App Development team on Upwork, with a 100% job success score and only 5-star reviews. Every Mobile App Developer on our team shares the same vision: to exceed expectations and deliver mobile products that drive impact. ✅ Helped 60+ companies build top-tier mobile apps ✅ 7+ years of hands-on Mobile App Development experience ✅ 40+ global partners supported in achieving digital success ✅ A collaborative team of 50 Mobile App Developers ✅ Top Rated Plus Mobile App Development agency ✅ 100% Job Success and consistent 5-star feedback ✅ Reliable, scalable, and high-performing mobile solutions 🔧 Services I Provide as a Mobile App Developer: Full-cycle Mobile App Development — from idea to deployment Native iOS & Android Development (Swift, Kotlin, Java) UI/UX Design tailored for Mobile App Users Performance Optimization by an experienced Mobile App Developer Secure API Integrations & Cloud Services Cross-Platform Solutions using Kotlin Multiplatform & Flutter Wearable & Bluetooth Device Integration for Mobile Applications Scalable Backend Connections for Mobile Infrastructure 🎯 Industries I Specialize in as a Mobile App Developer: 📦 E-Commerce Apps – built by a results-driven Mobile App Developer 🍔 Food & Drink Apps – delivered by a reliable Mobile App Developer 📚 Educational Apps – engaging experiences crafted by a Mobile App Developer 💪 Health & Fitness Apps – feature-rich apps from a Mobile App Developer 💘 Dating Apps – real-time systems designed by a top Mobile App Developer 🎬 Entertainment & Streaming – robust apps made by a skilled Mobile App Developer 💼 Finance & Banking – secure transactions with a professional Mobile App Developer 🌍 Travel Apps – GPS-powered journeys led by a seasoned Mobile App Developer 📱 SaaS Platforms – scalable systems by an enterprise-grade Mobile App Developer ⌚ Wearable Tech – Apple Watch & WearOS apps from a specialized Mobile App Developer 🚀 Advanced Features I Build as a Mobile App Developer: ✔️ Social Login (Google, Apple, LinkedIn) ✔️ Real-time Reviews & Feedback Systems ✔️ Offline Functionality & Data Syncing ✔️ Google & Apple Maps Integration ✔️ Real-Time Video Chat (WebRTC), Messaging & Push Notifications ✔️ Twilio Audio/Video/Chat Features ✔️ Monetization with AdMob, Facebook Ads ✔️ Bluetooth & Geofencing for Smart Devices 📩 Whether you’re a startup or enterprise, I’m the Mobile App Developer who can turn your vision into reality. Let’s connect and create something amazing together! 🚀 Our portfolio spans a wide range of industries, including fitness, healthcare, fintech, streaming, and e-commerce. We build robust applications that feature real-time functionality, Bluetooth and IoT integrations, GPS and mapping, secure API development, and cloud-connected solutions. Our team is also skilled in implementing advanced features such as in-app messaging, offline support, Firebase integration, AR experiences with ARKit, Jetpack Compose UI, and wearable tech, including WearOS and Apple Watch apps. We’ve developed for platforms like TVOS and Monkey-C (Garmin), and we bring a strong focus on product design, agile development, and smooth App Store/Play Store deployment. Whether you're a startup seeking a fast, flexible MVP or an enterprise aiming for long-term scalability, we offer global mobile app development expertise backed by 5-star client reviews and a commitment to building user-centric apps that perform at scale.
    Featured Skill Kotlin
    iOS
    Native App
    Android App
    Smart TV
    Smartphone
    Mobile App
    Mobile App Development
    Native App Development
    SwiftUI
    Android App Development
    Firebase
    Swift
    iOS Development
    Wear OS
  • $50 hourly
    • 5.0/5
    • (17 jobs)
    Dedicated Full-Stack Developer with 12+ Years of Experience in Java, Svelte, Next.js, and AWS I am a dedicated and passionate Full-Stack Developer with 12+ years of extensive experience in both web and mobile app development. With a proven track record of delivering high-quality, scalable solutions, I specialize in leveraging Java (Spring Boot), Svelte, Next.js, and AWS to build innovative applications that drive business success. With a keen eye for detail and a commitment to excellence, I have successfully executed numerous projects for startups, enterprises, and millions of end-users. My expertise spans back-end development, API integrations, and full life-cycle project management. A team player with a positive attitude, I excel both as an independent contributor and a collaborative team member. My strong communication and business acumen enable me to bridge the gap between technical teams and customers effectively. I have designed and implemented cutting-edge solutions in B2B and B2C sectors, consistently exceeding client expectations. Key Skills: Back-End Development: Advanced proficiency in Java (Spring Boot, Hibernate), Node.js and Python (Django, FastAPI). Front-End Development: Expertise in Angular, Vue.js, Next.js, React, and Svelte. Cloud Platforms: Skilled in AWS services (EC2, Lambda, S3, RDS) and Google Cloud. API Development: Strong experience in building and integrating RESTful and GraphQL APIs. Microservices Architecture: Proficient in designing and deploying scalable microservices. E-Commerce Platforms: Expertise in Shopify, BigCommerce and WordPress development. Project Management: Proven ability to lead complex projects from concept to delivery. Core Strengths: Scalability & Performance: Specialized in developing efficient, high-performing systems for large-scale applications. Modern Frameworks: Deep expertise in Svelte for building lightweight front-end applications and Next.js for server-side rendering. End-to-End Development: Adept at managing the full development lifecycle, ensuring quality and on-time delivery. Collaboration & Leadership: Skilled at fostering team collaboration and aligning technical solutions with business objectives. Career Highlights: Designed and implemented a robust microservices-based system using Spring Boot and AWS, enabling seamless scalability and high availability. Built a highly responsive, user-friendly front-end for a SaaS platform using Svelte and Next.js, improving customer retention by 25%. Migrated legacy applications to modern cloud-based architectures, reducing infrastructure costs by 30%. Led the development of a comprehensive API gateway, supporting millions of daily transactions for an enterprise client.
    Featured Skill Kotlin
    Vue.js
    Unity
    React
    Flutter
    Dart
    Java
    Ionic Framework
    Node.js
    JavaScript
    Objective-C
    Swift
    Angular
    TypeScript
    React Native
  • $38 hourly
    • 5.0/5
    • (2 jobs)
    I have experience creating apps for both Android and iOS, but I'm leaning towards Android. I've worked on simple e-commerce apps as well as complex projects with the use of AI (for example, my recent project related to baby monitoring). I'm a good team player and I like collaborating with fellow professionals to create great products.
    Featured Skill Kotlin
    Dagger 2
    Android SDK
    Swift
    Mobile App Development
    Retrofit
    Java
    Firebase
    Android
  • $50 hourly
    • 5.0/5
    • (10 jobs)
    I am a Senior Android Software Engineer with over 7+ years of commercial experience and a Bachelor’s degree in Computer Science. I specialize in end-to-end Android development, from concept to launch, with expertise in creating high-performance, scalable native apps in Kotlin and Java. Here’s what I bring to your project: - 𝗙𝘂𝗹𝗹 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 𝗟𝗶𝗳𝗲𝗰𝘆𝗰𝗹𝗲: I handle every stage, including planning, coding, testing, and deployment, ensuring smooth project flow and timely delivery. - 𝗕𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗳𝗿𝗼𝗺 𝗠𝗩𝗣 𝘁𝗼 𝗙𝘂𝗹𝗹 𝗦𝗰𝗮𝗹𝗲: I can create MVPs that validate your concept and iterate with new features to reach full functionality. - 𝗣𝗲𝗿𝗳𝗼𝗿𝗺𝗮𝗻𝗰𝗲 𝗢𝗽𝘁𝗶𝗺𝗶𝘇𝗮𝘁𝗶𝗼𝗻: I focus on efficient code and proactive optimizations to keep your app fast, responsive, and memory-efficient. - 𝗧𝗲𝘀𝘁𝗶𝗻𝗴: I ensure reliability through robust testing strategies, including unit tests, instrumentation and UI testing. - 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 & 𝗠𝗲𝘁𝗿𝗶𝗰𝘀: I integrate analytics and performance metrics, so you gain actionable insights into user behavior, engagement, and app performance. - 𝗣𝗿𝗼𝗯𝗹𝗲𝗺 𝗦𝗼𝗹𝘃𝗶𝗻𝗴: With years of experience troubleshooting, I quickly identify and resolve issues. Let’s collaborate to transform your app vision into a high-quality, user-focused Android experience that delivers real results!
    Featured Skill Kotlin
    Camera
    Android UI Design
    REST API
    Android Smartphone
    AI Chatbot
    Firebase
    Android SDK
    Android App Development
    Mobile App Development
    Android App
    Mobile App
    Artificial Intelligence
    Java
    Android
  • $32 hourly
    • 5.0/5
    • (6 jobs)
    🚀 Hey there! 𝐋𝐄𝐓'𝐒 𝐑𝐎𝐂𝐊 🚀 🌟 5-Star Reviews 🌟 8+ Years of Experience 🌟 Top-Notch Developers 🏆 Top 30 Mobile App Developers 🏆 Fluent English 🏆I have strong problem-solving skill ► Natife Team is a mobile app development company committed to delivering exceptional architecture, design, and software solutions tailored to each client's needs. We understand the individuality of every business, encompassing its structure, processes, values, and product vision. As a trusted partner, we facilitate business expansion through comprehensive IT consultancy, staffing, end-to-end mobile app development, and product enhancement services. As a mobile app developer, I’ve spent over 8 years mastering iOS app and Android app development—delivering intuitive, scalable experiences with a strong foundation in Swift and Kotlin. Whether it’s real-time health tracking or complex UI animation, I approach each project as a mobile app developer focused on performance and user satisfaction through high-quality mobile app development. As a mobile app developer, I’ve launched over 50 iOS apps and 40 Android apps, with millions of combined downloads and consistently high App Store ratings. From MVPs to enterprise-grade products, I’ve led mobile app development projects across fintech, wellness, logistics, and social networking. As a Smart Watch mobile app developer, I’ve created 10+ companion apps for Apple Watch and Wear OS. My experience includes building iOS apps that deliver precise workout data and Android apps that extend phone functionality to the wrist—ensuring cross-device continuity through cohesive mobile app development practices. In mobile app development, I use modern frameworks like SwiftUI and Jetpack Compose. As a hands-on mobile app developer, I’ve built apps with background processing, offline caching, and secure sync logic using REST APIs, enhancing the reliability of every iOS and Android app I deliver. As a mobile app developer, I’ve built over 40 iOS apps and 35 Android apps, delivering seamless user experiences across platforms and serving 5M+ users in 12+ industries, using consistent, scalable mobile app development principles. My portfolio as a healthcare mobile app developer includes iOS apps and Android apps used by 600,000+ patients in 12 countries to track vitals and book over 100,000 appointments. As a fintech mobile app developer, I developed iOS apps and Android apps that process $20M+ annually, with support for 30+ currencies and a 99.99% success rate in transactions. Acting as a productivity mobile app developer, I delivered iOS apps and Android apps that automate 70+ workflows, manage 500,000+ tasks, and increase team efficiency by 40%. As a logistics mobile app developer, I built scalable iOS apps and Android apps supporting 1.2M+ live bookings in 60+ cities, with 98% uptime and real-time GPS tracking powered by robust mobile app development infrastructure. In my role as a streaming mobile app developer, I launched iOS apps and Android apps serving 800,000+ monthly active users, offering <100ms latency and offline playback—driven by performance-optimized mobile app development workflows. As a lifestyle mobile app developer, I created iOS apps and Android apps downloaded 2M+ times, boosting daily user engagement by 45% through wellness and social features—crafted with user-centric mobile app development in mind. As a weather mobile app developer, I launched iOS apps and Android apps with real-time forecasting for 100,000+ concurrent users, delivering updates in <500ms through efficient, API-driven mobile app development. As a fitness mobile app developer, I developed iOS apps and Android apps tracking workouts and syncing with 10+ wearable devices, logging millions of activity minutes. As a restaurant mobile app developer, I created iOS apps and Android apps for 150,000+ users, with GPS delivery tracking and loyalty features increasing retention by 25%. As a hotel booking mobile app developer, I designed iOS apps and Android apps used to book over 500,000 room nights across 20+ countries, with real-time confirmation. As a TVOS mobile app developer, I built iOS apps and Android apps supporting IPTV and VOD streaming with 260+ channels and 100K+ monthly viewers. As an e-commerce mobile app developer, I engineered iOS apps and Android apps featuring 1M+ product listings, handling 50K+ daily transactions with secure checkouts. As a vehicle tracking mobile app developer, I created iOS apps and Android apps that log 2M+ km/month, update routes every 10 seconds, and serve 50 K vehicles. As a doctor booking mobile app developer, I developed iOS apps and Android apps that manage 300,000+ secure appointments, with calendar sync and encrypted messaging. As a dating mobile app developer, I delivered iOS apps and Android apps with 3M+ matches, 100K+ daily chats, and location filters across 40+ cities—each designed with scalable mobile app development frameworks.
    Featured Skill Kotlin
    Android
    Mobile App Design
    iOS
    Native App
    Android App
    Smartphone
    Smart TV
    SwiftUI
    Android App Development
    Firebase
    Mobile App
    Swift
    Mobile App Development
    Native App Development
  • $35 hourly
    • 5.0/5
    • (14 jobs)
    𝐈𝐬 𝐲𝐨𝐮𝐫 𝐬𝐨𝐟𝐭𝐰𝐚𝐫𝐞 𝐡𝐨𝐥𝐝𝐢𝐧𝐠 𝐲𝐨𝐮 𝐛𝐚𝐜𝐤 𝐟𝐫𝐨𝐦 𝐬𝐜𝐚𝐥𝐢𝐧𝐠 𝐨𝐫 𝐩𝐞𝐫𝐟𝐨𝐫𝐦𝐢𝐧𝐠 𝐚𝐭 𝐢𝐭𝐬 𝐛𝐞𝐬𝐭? With over 7 years of experience as a Java Developer, I specialize in solving complex technical challenges and transforming ideas into efficient, scalable, and impactful solutions. Whether it’s optimizing your existing systems, building microservices, or leading teams toward exceptional quality, I bring the technical expertise and strategic insight your projects need to succeed. 𝗣𝗿𝗼𝗳𝗲𝘀𝘀𝗶𝗼𝗻𝗮𝗹 𝗘𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲: ➡Over 6 years of hands-on experience in software projects development, utilizing Object-Oriented Analysis (OOA), Object-Oriented Design (OOD), and Object-Oriented Programming (OOP) principles. ➡ Proficient in designing and implementing Client-Server and Multi-Tier architectures. ➡ Worked in diverse technological domains such as healthcare, fintech, and cloud computing, showcasing adaptability and versatility. 𝗟𝗲𝗮𝗱𝗲𝗿𝘀𝗵𝗶𝗽 𝗮𝗻𝗱 𝗙𝗼𝗰𝘂𝘀: ➡ Successfully played the role of a tech lead, demonstrating leadership skills in guiding teams towards achieving high development standards. ➡Prioritized and maintained a focus on quality throughout the development lifecycle. ➡Strived for enhanced productivity by implementing efficient development practices. 𝐏𝐫𝐨𝐠𝐫𝐚𝐦𝐦𝐢𝐧𝐠 𝐋𝐚𝐧𝐠𝐮𝐚𝐠𝐞𝐬 & 𝐅𝐫𝐚𝐦𝐞𝐰𝐨𝐫𝐤𝐬 ✅Languages: Java, Java 8, Java 11, Java EE, Java SE, JavaFX, SQL, JSON, XML, YAML. ✅Frameworks: Spring (Spring Boot, Spring MVC, Spring Data, Spring Cloud, Spring Security, Spring AOP, Spring Batch, Spring WebFlux), Quarkus, Hibernate, JPA. ✅Design Paradigms: OOA (Object-Oriented Analysis), OOD (Object-Oriented Design), OOP (Object-Oriented Programming). 𝐓𝐞𝐜𝐡𝐧𝐨𝐥𝐨𝐠𝐢𝐞𝐬 & 𝐓𝐨𝐨𝐥𝐬 ✅Databases: MySQL, PostgreSQL, MongoDB, Redis, DynamoDB. ✅Cloud Platforms: AWS (EC2, S3, SQS, SNS, Lambda, IAM, CloudFormation), Azure (Virtual Machines, Storage, Functions, App Services), OpenShift. ✅DevOps & CI/CD: Docker, Kubernetes, Helm, Jenkins, Terraform, Maven, Gradle, Git (GitLab, Bitbucket, GitFlow). ✅Messaging & APIs: Kafka, RabbitMQ, REST APIs, SOAP, gRPC, API Gateway, WebSockets. ✅Authentication & Security: OAuth2, JWT. 𝐀𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐚𝐥 𝐏𝐚𝐭𝐭𝐞𝐫𝐧𝐬 & 𝐃𝐞𝐬𝐢𝐠𝐧 𝐏𝐫𝐢𝐧𝐜𝐢𝐩𝐥𝐞𝐬 ✅Architectures: Microservices, Monolithic architecture, SOA (Service-Oriented Architecture), Event-driven architecture. ✅Design Patterns: CQRS, Saga pattern, Circuit breakers, Service discovery, Distributed systems, Distributed tracing. ✅Principles: SOLID principles, Clean code. 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 𝐏𝐫𝐚𝐜𝐭𝐢𝐜𝐞𝐬 & 𝐌𝐞𝐭𝐡𝐨𝐝𝐨𝐥𝐨𝐠𝐢𝐞𝐬 ✅Testing: Unit testing, Integration testing, JUnit, Mockito, TestNG. ✅Development Methodologies: TDD (Test-Driven Development), BDD (Behavior-Driven Development), Agile (Scrum, Kanban). ✅Version Control: Git, GitLab, Bitbucket. 𝐎𝐩𝐭𝐢𝐦𝐢𝐳𝐚𝐭𝐢𝐨𝐧 Performance optimization, Code refactoring, Code reviews, Database query optimization. 𝐀𝐫𝐞𝐚𝐬 𝐨𝐟 𝐀𝐜𝐭𝐢𝐯𝐢𝐭𝐲 Backend development, Web development, Full-stack development, API development, Cloud engineering, Data engineering. 𝐈𝐧𝐝𝐮𝐬𝐭𝐫𝐢𝐞𝐬 Financial services, healthcare, e-commerce, enterprise applications, cloud computing, telecommunications, logistics, travel and hospitality, media and entertainment, automotive, blockchain, IoT, Saas, retail.. 𝐒𝐩𝐞𝐜𝐢𝐚𝐥𝐢𝐳𝐚𝐭𝐢𝐨𝐧𝐬 & 𝐑𝐨𝐥𝐞𝐬 Backend developer, Java developer, Senior Java developer, API developer, Full-stack developer, Android developer, Java networking expert. 𝐓𝐲𝐩𝐞𝐬 𝐨𝐟 𝐒𝐞𝐫𝐯𝐢𝐜𝐞𝐬 Java development services, Backend development, API integration, Cloud computing services, Performance tuning, Code audits and reviews, SaaS application development. Are you prepared to elevate your software to new heights? Let's discuss how I can infuse strategic innovation and technical excellence into your projects. 16/12
    Featured Skill Kotlin
    REST API
    Hibernate
    JavaFX
    Spring Framework
    Microsoft Azure
    Amazon Web Services
    Docker
    PostgreSQL
    RESTful API
    MySQL
    Spring Boot
    Back-End Development
    Software Development
    Java
  • $35 hourly
    • 5.0/5
    • (16 jobs)
    Hello! My name is Victoria, and I am an experienced mobile app and website developer with over 5 years of professional experience. I take pride in being a member of the ELDEVELOP team, where every day I encounter exciting challenges and opportunities in the world of mobile development and web technologies. In my career, I have focused on development for both mobile devices and websites, including e-commerce sites. In mobile development, I am proficient in the programming languages Swift and Kotlin, creating innovative and high-performance applications for iOS and Android platforms. In web development, I use PHP and frameworks like CakePHP to build powerful and scalable web applications. I also have experience working with Node.js to create efficient server applications. My skills also encompass using content management systems like WordPress and developing interfaces using HTML and CSS3. At ELDEVELOP, I have learned to appreciate teamwork, innovation, and a commitment to high product quality. My goal is to continue contributing to the company's success by developing outstanding solutions that meet client requirements and leave a lasting impression on users. I look forward to the opportunity to contribute to your project and leverage my experience to create unique and effective solutions for you and your company!
    Featured Skill Kotlin
    Node.js
    Swift
    Mobile App Development
    WordPress
    CakePHP
    PHP
    Web Development
    Ecommerce Website
    iOS
    Android
    Mobile Web
  • $32 hourly
    • 5.0/5
    • (6 jobs)
    🚀 Native Mobile App Developer | Kotlin • Swift • Android • iOS • Mobile App Development 👋 Hi! I'm Yehor — a Native Mobile App Developer with 8+ years of experience in Mobile App Development. I’ve delivered over 50 successful iOS and Android apps with flawless performance and beautiful UX. As a Top Rated Mobile App Developer on Upwork with 30+ five-star reviews, I help startups and enterprises launch scalable, future-proof mobile products. From real estate, fitness, and meditation apps to e-commerce, logistics, and booking platforms, my Mobile App Development skills cover every business niche. Whether you’re building a new iOS or Android solution — or optimizing your current Mobile App Development lifecycle — I bring precision, speed, and creativity to the table. ✅ What I Offer as a Mobile App Developer: 🧠 Product Design & Development: Full-cycle Mobile App Development from prototype to store release Interactive prototypes, animations, user onboarding, and localization UI/UX design via Figma, Sketch, and Adobe XD 🛠️ Native iOS & Android Development: As a dual-platform Mobile App Developer, I work with: Swift, SwiftUI, RxSwift, Objective-C for iOS Development Kotlin, Jetpack Compose, Java for Android Development Mobile App Development for tablets, Apple Watch, Wear OS, and Apple TV Biometric authentication, AR, NFC, QR scanners, and push notifications 📊 Scalable Architecture & Integrations: REST APIs, Firebase, Core Data, MongoDB, Realm, SQLite SDK integration, analytics tools, real-time collaboration, cloud sync Support for third-party services, mobile game development, CMS & monetization ☁️ Cloud & Backend Services: Mobile App Development powered by AWS, Google Cloud, GitLab, Bitbucket CI/CD pipelines with Fastlane, TestFlight, App Store Connect Secure and scalable mobile backend microservices Mobile network optimization, clean code practices, MDM, and version control 📲 Business-Focused Mobile Solutions: As a Mobile App Developer, I focus on: Performance optimization and session management Voice assistant integration (Siri, Google Assistant, Alexa) Data visualization, geolocation, GPS, wearable support Custom onboarding flows, accessibility features, retention strategies 💬 Ready to Launch Your Next App? Let’s build your iOS or Android app with world-class Mobile App Development skills. Whether you're a startup in need of an MVP or an enterprise scaling globally — I'm the Mobile App Developer who can take your vision to the app stores. 📱 Over 15+ industries served — including fitness, real estate, e-commerce, salon, blockchain, chat apps, audio & video platforms, and more. ⏳ Let’s talk today — and turn your idea into a powerful iOS/Android Mobile App Development success story. 📩 Drop a message — your trusted Mobile App Developer is just one click away.
    Featured Skill Kotlin
    JetPack
    iOS SDK
    Mobile App Design
    Mobile App Development
    Mobile App Bug Fix
    Native App Development
    AI App Development
    Android App Development
    iOS Development
    SwiftUI
    Swift
    iOS
    Mobile App
    Android
  • $45 hourly
    • 5.0/5
    • (2 jobs)
    I am a seasoned mobile app developer with over 8 years of experience designing, developing, and deploying cutting-edge mobile applications for both Android and iOS platforms. My specialty is integrating advanced AI technologies to create intelligent, user-centric apps. ✔ Mobile Development: Swift, Kotlin, Java, Flutter, and React Native. ✔ Backend Development: Knowledgeable in Node.js, Django, and Firebase for robust backend support. ✔ AI Integration: Experienced with machine learning frameworks such as TensorFlow, PyTorch, and Core ML. Skilled in implementing natural language processing, computer vision, and predictive analytics. ✔ UI/UX Design: Strong focus on creating intuitive and engaging user interfaces using Sketch, Figma, and Adobe XD. ✔ Project Management: Adept at Agile methodologies, version control (Git), and continuous integration/continuous deployment (CI/CD). If you are looking for a dedicated and professional full stack developer to build web & mobile applications, let's connect and discuss details about your project.
    Featured Skill Kotlin
    Android
    Firebase
    FlutterFlow
    SwiftUI
    Flutter
    React Native
    Mobile App Development
    iOS Development
    Swift
    PostgreSQL
    JavaScript
    React
    Node.js
    Java
  • $40 hourly
    • 5.0/5
    • (6 jobs)
    👋 Greetings, Ready to boost your ideas with AI-integration, Machine Vision, or LLM? Glad to hear from you! I`m an experienced Senior Java developer / Team lead with over 9 years of hands-on experience in web | mobile applications in different domains: ✔️ e-commerce, ✔️ FinTech, ✔️ SaaS etc. My Specialization: ✅ Java experience 9 years: Widely utilizing recent Java features, including Lambdas, Stream APIs, DateTime APIs, and Functional Interfaces. ✅ AI integration, Computer vision, LLM training. ✅ Java EE: RESTful Services, SOAP Services, JPA, Hibernate, API Integration etc. ✅ Spring experience 9 years: Spring Core, Spring Boot, Spring Data, Spring Cloud, etc. ✅ Other "frameworks": Keycloak authorization, JHipster, Swagger, Liquibase, Axon, Vaadin ✅ SQL Databases experience over 9 years: PostgreSQL, MySQL, MariaDB, Oracle ✅ NoSQL Databases: MongoDB, Redis, Hazelcast ✅ Message Broker: Kafka and Zookeeper ✅ Firebase messaging ✅ Message Queues: ActiveMQ & RabbitMQ. ✅ ELK: logstash, elasticsearch, kibana ✅ Testing: JUnit, Spring Test, Mockito, Integration Test, Unit Test. ✅ Versioning: GIT, GitHub, BitBucket, GitLab etc ✅ DevOps: Jenkins, Docker, Kubernetes, CI/CD ✅ Hands-on design, development, implementation, and optimization of the application. ✅ Apply software engineering best practices incl. design review, code review, and refactoring. ✅ Experienced with the full Software development life cycle (SDLC) including gathering requirements, development (design, coding, debugging), testing & deployment I`m glad to be involved in your project and do my best to reach maximum impact 🚀
    Featured Skill Kotlin
    OAuth
    Web Application
    Mobile App
    Web Development
    Spring Boot
    RabbitMQ
    MongoDB
    SQL
    Hibernate
    Spring Framework
    Database
    Microservice
    API
    Java
  • $40 hourly
    • 5.0/5
    • (8 jobs)
    I am a Senior Full Stack Developer with 6+ years of experience in the following technologies and languages providing digital solutions for my clients with 100% satisfaction. ✔️ Backend (Django, Flask, Fast API, Node.js, Nest.js, PHP, Laravel, Yii, CodeIgnitor) ✔️ Frontend (Angular, React.js Next.js, Vue.js, Nuxt.js, Svelte, JavaScript, TypeScript) ✔️ Language (Python, R, C++, Java) ✔️ Technology (NLP, LLM, Chatbot, ChatGPT, Voice AI, Computer Vision, Deep Learning) ✔️ Framework (PyTorch, TensorFlow, Keras, OpenCV, NLTK/Spacy, NumPy, Pandas) ✔️ AI Tools (ChatGPT, RAG, OpenAI, Generative AI, LangChain, LLM, Vertex AI) ✔️ Database (MySQL, MSSQL, MongoDB, PostgreSQL, GraphQL) ✔️ DevOps (Git, Azure, AWS, Docker, Jira, Kubernetes, Google Clouds)
    Featured Skill Kotlin
    JavaScript
    IOStoken
    Shopify
    WordPress
    React Native
    Swift
    Android
    Node.js
    React
    Flask
    Django
    Ruby on Rails
    PHP
    Python
  • $60 hourly
    • 5.0/5
    • (2 jobs)
    Hi everyone, I am a senior mobile and web fullstack developer with over 6 years of experience in React/Vue, React Native, NextJS, Flutter, Swift, Java, Kotlin. React : 9.5/10, +6 years Vue: 9.5/10, +6 years React Native: 9.5/10, + 6 years NextJS: 9/10, +5 years Flutter: 9/10, +5 years Swift/SwiftUI: 9/10, +5 years Java/Kotlin: 8/10, +4 years TailwindCSS: 9/10, + 5 years Typescript: 9/10, + 5 years Node/Firebase: 9/10, +6 years Also, I’m hands-on with project architecture, always considering the best technology and approach to optimize time, resources, and costs. My expertise covers a wide range of technologies, including JavaScript/TypeScript, ReactJS/VueJS, and NodeJS, in both front-end and back-end development. I am available to work full time in any timezone. Let's get in touch. Thank you.
    Featured Skill Kotlin
    Vue.js
    Node.js
    AWS Amplify
    Firebase
    Web Development
    iOS Development
    Android App Development
    SwiftUI
    Swift
    Flutter
    Redux
    React Native
    React
    Java
  • $45 hourly
    • 5.0/5
    • (70 jobs)
    I'm 16 years in mobile development, so I know what makes apps grow - and what kills them! I build clean, scalable mobile apps that actually grow your revenue 💸 Because if your product wins, we both win Apps I’ve built have: 📱 Hit 10M+ downloads 💰 Helped raise $5M+ ⭐️ Averaged 4.8+ ratings on the App Store & Google Play 🧠 900K+ monthly active users in mental health, productivity & social apps 🚀 Time-to-market cut by 30% thanks to scalable Flutter architecture 🛠️ 80+ production apps shipped, from MVPs to enterprise-grade tools 🏦 Trusted by Bank of America, Citibank, Netflix, Spotify Core Skills: ☑️ Cross-Platform: Flutter, React Native, Compose Multiplatform ☑️ iOS: Swift, Objective-C, SwiftUI, UIKit ☑️ Android: Kotlin, Java, Jetpack Compose ☑️ Backend: FastAPI, Django, Spring Boot, Node.js ☑️ Tools: Firebase, Stripe, Google Maps, RESTful APIs, CI/CD, Git, Figma Let’s build an app that actually grows your business - not just dev bill. Drop me a message. Let’s talk.
    Featured Skill Kotlin
    Flutter Stack
    Mobile Development Framework
    Mobile App
    Android
    iOS
    AI Mobile App Development
    Mobile App Improvement
    Mobile App Development Consultation
    Mobile App Development
    Python
    Swift
    Android App Development
    iOS Development
    Flutter
  • $40 hourly
    • 5.0/5
    • (16 jobs)
    I am a Top-rated developer to bring all your product ideas into a success story. My experience in mobile software and web development field is ready to serve your business. I was working on Healthcare and Fitness apps, social and e-commerce solutions. There is a lot of experience in (but not limited to) Finance, Education, Travel and other entertaining and business apps. If you need a mobile app or website I'm happy to provide you with the solution. I have an extensive background in leading and driving all phases of software projects and client engagements with the largest brands as well as with tiny startups. Key facts: • Good references and happy clients, • Successful apps on the marketplaces, • Software Development Experience – over 15 years • Mobile Software Development • Web Development Software development is my passion. I achieve high quality of products with proven software development process. I can work both as individual and as a part of software agency which gives you bigger opportunities for scaling the work. Over the time has built various complex solutions for a diverse range of businesses and industries (Health&Fitness. IoT, Finances, Retail, IT management, e-Commerce, Marketing&Advertising, Transport&Logistics, Media&Publishing, Social networks, Entertainment). Sergey and his team can guarantee the highest quality of our services, quick turnaround, professional communication and 24/7 Skype/email support for our clients. Please get in touch with me for our references or to request a quote.
    Featured Skill Kotlin
    Health & Fitness
    Apple Watch
    Front-End Development
    Healthcare IT
    Swift
    React
    PHP
    iOS Development
    watchOS
    React Native
    HealthKit
    Android
    iOS
  • $45 hourly
    • 5.0/5
    • (21 jobs)
    I am the founder of Nitrix, a software development company. I have specialized in web and mobile development for more than 10 years and now I can offer you a team of outstanding developers who can create excellent IT solutions for you and your business! Your idea will be realized with an attractive UI/UX design and a clean code that is easy to read, support, and implement additional functions. As a progressive software development company, we aim to create the most comfortable, smooth, and stable products for millions of users. Our specialists have developed different services and apps of various scales, importance, and spheres (medicine-related services, uber-like and dating apps, streaming services, news apps, etc). We have a solid understanding of the whole process of the software development cycle so your request will meet all modern requirements and standards. You can check our portfolio and reviews from previous clients below, so do not hesitate to write to me and we will discuss the reason that brought you here! Technologies we use: Flutter, Dart, Swift, Objective-C, Kotlin, Java, C#, JavaScript, PHP, MySQL, iOS SDK, CarPlay, tvOS, watchOS, Android SDK, Android Auto, Android TV, Wear OS, Google Chromecast, ExoPlayer, FFmpeg, RESTful, Sockets and many more!
    Featured Skill Kotlin
    Streaming Platform
    Web Development
    IPTV
    Web Design
    UX & UI
    Apple Watch
    Dart
    tvOS
    iOS Development
    iOS
    Android
    Swift
    Flutter
    Android App Development
  • $35 hourly
    • 5.0/5
    • (21 jobs)
    Full-cycle iOS and Android Application development agency from Zaporizhzhya, Ukraine. Website-portfolio: [please ask for the link] Full-cycle means that we provide services at every stage of iOS and Android application development process. We grow our business by helping our customers to grow theirs. We build iOS apps (iPhone, iPad) and Android apps (phone and tablet) of any complexity or style (material style, flat style): - delivery and ordering systems related applications - logistics mobile applications - marketplace apps - video and chat applications, WebRTC / VoIP, socket connection - booking mobile apps - online TV applications - educational applications - applications for online stores - cleaning services - in-app purchases and in-app subscriptions related apps - iOS apps with iOS specific features - Android material apps with Android specific features - AndroidTV applications - you tell it - we do it iOS skills include but not limited to: - Swift 3 / Objective-C - iOS SDK, xCodeb - Protocols: JSON-RPC, XML, RPC, SOAP, REST. - Integration with existing social networks: Facebook, Twitter, Vkontakte, G+ - 2D games: Cocos2D, Cocos2Dx - E-books (static or interactive), Newsstand - Databases: SQLite, CoreData - BLE 4.0 - Mobile advertisement: iAd, AdMob, AppLeads, Flurry, AdWhirl - Other servises and SDKs: Braintree, Liqpay, Yandex.Money, Branch, Maps (OSM, Google, Apple), LinPhone, FrozenMountain, ooVoo, Flurry Analytic, Google Analytics, Crashlytics, Test Flight, other Android: - Java / Kotlin - Encryption: OpenGPG. - Protocols: JSON-RPC, XML-RPC, SOAP, TCP/IP. - simple applications OpenGL ES - Integration with social networks (Facebook, Twitter, Vkontakte, MailRu, Odnoklassniki), Google services (e.g. Youtube, Google Cloud Printing), Payment gateways (Braintree, PayPal, Liqpay, Yandex.Money) - Interaction with external devices (BLE 4.0/SPP/USB). - Android SQLite - Google Billing, in-apps - VoIP and WebRTC integrations React Native skills: - TypeScript - Node.JS (MERN stack) - JavaScript - Redux, - ES6+ - MongoDB - HTML5, React, CSS - Redux - Material UI Web technologies stack: - React.js, - Angular.JS, Angular 2+ - Laravel (PHP framework), - Symfony (PHP framework), - Node.JS, - VueJs - Express.js, - Bootstrap, - Jquery - Integration with social networks (Facebook, Twitter, Vkontakte, MailRu, Odnoklassniki), Google services (e.g. Youtube, Google Cloud Printing), Payment gateways (Braintree, PayPal, Liqpay, Yandex.Money) - Protocols: JSON-RPC, XML-RPC, SOAP, TCP/IP and much much more. You come to us with an abstract idea and after time we’ll submit a fully functional app to AppStore or Google Play Market. We create Tech Specs documentation, mockups, app designs, development itself, application updates as well as upgrades, along with many other services more or less connected with iOS and Android development.
    Featured Skill Kotlin
    Web Development
    Vue.js
    App Development
    User Interface Design
    iPad App Development
    Mobile UI Design
    Swift
    Flutter
    React
    Node.js
    iOS Development
    Mobile App Development
    Android App Development
    Android
  • $35 hourly
    • 4.9/5
    • (38 jobs)
    ʜɪ! ᴀʀᴇ ʏᴏᴜ ʟᴏᴏᴋɪɴɢ ꜰᴏʀ ᴀ ᴛᴇᴀᴍ ꜰᴏʀ ᴅɪɢɪᴛᴀʟ ᴘʀᴏᴅᴜᴄᴛ ᴄʀᴇᴀᴛɪᴏɴ? ɪ ʜᴇᴀᴅ ᴀ ᴛᴇᴀᴍ ᴏꜰ ᴇxᴘᴇʀᴛꜱ ɪɴ ᴡᴇʙ ᴀɴᴅ ᴍᴏʙɪʟᴇ ᴀᴘᴘ ᴅᴇꜱɪɢɴ ᴀɴᴅ ᴅᴇᴠᴇʟᴏᴘᴍᴇɴᴛ. ꜱᴛᴀᴄᴋ ᴏꜰ ᴛᴇᴄʜɴᴏʟᴏɢɪᴇꜱ ᴡᴇ ᴜꜱᴇ: ✔️ ꜰʀᴏɴᴛ-ᴇɴᴅ: ʀᴇᴀᴄᴛ, ᴠᴜᴇ.ᴊꜱ, ᴀɴɢᴜʟᴀʀ ✔️ ʙᴀᴄᴋ-ᴇɴᴅ: ᴘʜᴘ, ʟᴀʀᴀᴠᴇʟ, | ɴᴏᴅᴇ.ᴊꜱ, ɴᴇꜱᴛ.ᴊꜱ | ᴄʀᴇᴀᴛɪɴɢ ᴀᴘɪ ✔️ ᴍᴏʙɪʟᴇ: ꜰʟᴜᴛᴛᴇʀ, ʀᴇᴀᴄᴛ ɴᴀᴛɪᴠᴇ ✔️ ᴜɪ/ᴜx ᴅᴇꜱɪɢɴ ✔️ ᴅᴇᴠᴏᴘꜱ ✔️ Qᴜᴀʟɪᴛʏ ᴀꜱꜱᴜʀᴀɴᴄᴇ ᴡᴇ ᴏꜰꜰᴇʀ ᴀ ʜɪɢʜ ʟᴇᴠᴇʟ ᴏꜰ ꜱᴇʀᴠɪᴄᴇ: 🙋‍♀️ 🙋‍♂️ ʀᴇꜱᴘᴏɴꜱɪʙʟᴇ ᴀɴᴅ ᴅᴇᴛᴀɪʟꜱ ᴀᴛᴛᴇɴᴛɪᴠᴇ ᴘʀᴏᴊᴇᴄᴛ ᴍᴀɴᴀɢᴇʀꜱ 👩‍🎨👨‍🎨 ᴄʀᴇᴀᴛɪᴠᴇ ᴀɴᴅ ᴏᴜᴛ-ᴏꜰ-ᴛʜᴇ-ʙᴏx ᴛʜɪɴᴋɪɴɢ ᴅᴇꜱɪɢɴᴇʀꜱ 👨‍💻 👩‍💻 ɢᴇɴɪᴜꜱ ᴘʀᴏꜰᴇꜱꜱɪᴏɴᴀʟ ᴅᴇᴠᴇʟᴏᴘᴇʀꜱ 👩‍🔧👨‍🔧 ᴍᴇᴛɪᴄᴜʟᴏᴜꜱ Qᴀ ᴇxᴘᴇʀᴛꜱ ᴅᴏɴ'ᴛ ʜᴇꜱɪᴛᴀᴛᴇ ᴛᴏ ᴛᴇxᴛ ᴍᴇ - ɪ'ʟʟ ʙᴇ ɢʟᴀᴅ ᴛᴏ ʜᴇʟᴘ ʏᴏᴜ!
    Featured Skill Kotlin
    Swift
    React Native
    Web Service
    Java
    Python
    Laravel
    PHP
    CakePHP
    Yii
    Node.js
    React
    JavaScript
    WordPress
    CSS
  • $45 hourly
    • 5.0/5
    • (60 jobs)
    With over 9 years of experience as a Mobile Developer, I bring to each project: ✓ Steadfast Commitment to Quality: Upholding the principle that excellence is the only standard, I approach every project with meticulous care and precision, ensuring outcomes that are not just completed, but masterfully executed. ✓ Passion for New Technologies: My enthusiasm for innovation drives me to continuously explore and integrate the latest trends and advancements in mobile development, keeping my solutions at the forefront of technology. ✓ Holistic Approach: Balancing innovation with reliability, I deliver projects that exceed client expectations, merging cutting-edge technology with dependable performance to create impactful solutions. ✓ Drive for Challenges: The dynamic and ever-evolving landscape of mobile development fuels my pursuit of new challenges and opportunities. Leveraging my extensive skills, I strive to make a significant difference in the mobile technology sphere, pushing boundaries and contributing to projects that set new benchmarks.
    Featured Skill Kotlin
    Android UI Design
    RESTful API
    Google Maps API
    JSON
    Core Java
    XML
    Android SDK
    Android App Development
    iOS Development
    Swift
    iOS
    Android
    Java
    Firebase
  • $50 hourly
    • 5.0/5
    • (17 jobs)
    You are here because you need a web application - not just a mediocre website, but a complex mechanism tailored to your specific business needs that's just above the competence level of most freelancers out there? If yes, search no further. That's what I've been doing for the last 15 years. Contact me if your needs include: - Custom integrations with third-party APIs; - A mobile app that perfectly reflects and automates your business process and complements your web app; - Collecting and processing data from other websites; - High-load web applications designed to handle thousands of requests per second; - Applications with industry-specific business logic in financial, logistics, travel, healthcare, entertainment or media fields; - Mobile optimized, performance-optimized and SEO optimized websites; - Advanced eCommerce applications; and you are looking for someone who: - understands the UI/UX practices that websites use to attract, convert and retain customers; - speaks fluent, easily understandable English; - is ready to adjust to your business hours; - is attentive to detail; - always keeps you updated about the progress; - is easy-going and agreeable. I'm looking forward to learning about your goals and helping you achieve them. Sincerely, Serhiy
    Featured Skill Kotlin
    Artificial Intelligence
    iOS
    Swift
    Blockchain
    User Experience Design
    Node.js
    JavaScript
    Shopify
    Laravel
    HTML
    WordPress
    React
    PHP
    Vue.js
  • $45 hourly
    • 5.0/5
    • (25 jobs)
    I can develop any kind of mobile application for you. My primary skill is Android development, and I can gather a team of professionals to cover all aspects of application development, including backend, design, iOS, and frontend. I have developed more than 30 apps, and all of my clients are satisfied with the results. My stack ✔Kotlin, Java ✔Clean Architecture, MVVM, MVP ✔Jetpack, Coroutines, Dagger2/Hilt, Room, Retrofit, Glide, Firebase, Payments Tools I use: ✔Android Studio ✔Sketch, Adobe Photoshop, Figma, Adobe Illustrator Have any questions? Want to discuss your projects? Feel free to contact me and have a nice day! :-)
    Featured Skill Kotlin
    XML
    Android SDK
    Dagger 2
    Android
    Firebase Cloud Firestore
    Android App Development
    JetPack
    Android Room Persistence
    Multithreaded Programming
    Push Notifications
    Retrofit
    Firebase
    SQLite
    Java
    Android Studio
  • $40 hourly
    • 4.9/5
    • (33 jobs)
    I'm a part of a skilled Android and iOS development team based in Ukraine, right in the heart of Europe. From MVPs to fully featured apps, we focus on clean UI, fast load times, and scalable architecture. We’ve built: 🎧 Audiobook apps with reward systems + admin panel 💪 Fitness apps with personalized plans & video workouts 🐾 Pet tech platforms connecting dog owners with care services ❤️ Dating apps with safety features, real-time chat, and location tools We handle everything from design to backend to launch—and we’re great to work with. Let’s build something awesome!
    Featured Skill Kotlin
    Svelte
    Android App
    Apple Watch
    Chat & Messaging Software
    Native App Development
    User Profile Creation
    Tablet
    iOS
    Smartphone
    Flutter
    Mobile App Development
    Android App Development
    iOS Development
    Swift
  • $50 hourly
    • 5.0/5
    • (21 jobs)
    I'm a mobile app developer with over 8️⃣ years of experience, and I love turning ideas into awesome apps. Outside of Upwork, I've launched 2️⃣0️⃣+ projects, so I've a good handle on building successful mobile experiences. I specialize in native iOS and Android but am also comfortable with cross-platform solutions. What I Do: 📱 Native iOS & Android app development (Swift, Kotlin) 🛠️ Cross-platform development (React Native, Flutter) ⚙️ Backend & API integration (Firebase, AWS, REST API) ✨ UI/UX design (Figma, Sketch) My Promise to You: 💬 Open and honest communication (regular updates, no surprises!) 🎯 Focus on your vision (I'll make sure your app matches your goals) 🐞 Quick and efficient bug fixes (because nobody likes glitches) I Can Help With: 🚀 Building your app (iOS, Android, or both!) 🔗 Connecting your app to backend systems 💡 Creating mobile solutions in Health & Lifestyle, Social, Business, EdTech and AI niches Let's Chat! 💬 📌 Don't hesitate to invite me at least for the best consulting Mobile App Development, iOS Development, Android Development, Cross-Platform Development, Flutter Development, Kotlin Development, Swift Development, Java Development, Software Development Agency, Full-Cycle Development, MVP Development, Product Development, App Maintenance, Software Consulting, Agile Development, API Integration, Backend Development, Cloud-Based Solutions, SaaS Development, UI/UX Design, HealthTech App Development, FinTech App Development, EdTech Solutions, E-commerce Mobile Apps, Social Media Apps, IoT Mobile Development, AI-Powered Apps, Accessibility Solutions, GPS & Location-Based Apps, Mobile Security & Encryption, REST API, Firebase, Google Cloud, AWS, BLE (Bluetooth Low Energy), Custom UI Development, Mobile App Security, Payment Gateway Integration, AI & Machine Learning, AR/VR
    Featured Skill Kotlin
    Swift
    AI Mobile App Development
    AI App Development
    Bluetooth
    Healthcare IT
    Flutter
    Native App Development
    Android
    iOS
    Mobile App Improvement
    Mobile App Bug Fix
    Mobile App Development Consultation
    Mobile App Development
    Mobile App
  • $40 hourly
    • 4.9/5
    • (12 jobs)
    🇺🇦 🤝 Struggling to find a reliable native app team? Let’s build your app – fast, secure & scalable! Top Rated | 8+ Years in Mobile App Development | 50+ Projects | 30+ Reviews | 100% Job Success 💪 We’re NATIFE, a senior-level team in Mobile App Development, focusing on native solutions with Swift and Kotlin. From MVPs to large-scale ecosystems – we’ve helped 50+ clients grow their businesses through effective Mobile App Development tailored to real market needs. 🚀 Why clients choose us: 1. End-to-end Mobile App Development ✔️ Full-cycle Mobile App Development for iOS & Android using SwiftUI, Jetpack Compose, HealthKit, GPS, NFC, and more. ✔️ Our Mobile App Developers strictly follow App Store Guidelines, ensuring smooth publishing and updates. ✔️ Specialized in TV & Watch apps, IPTV/OTT, and wearable devices – true native Mobile App Development beyond smartphones. 2. Backend & cloud excellence for Mobile ✔️ Scalable backends with Node.js, MongoDB, Firebase, AWS, GCP – all tailored for high-performing mobile app development. ✔️ Enterprise-grade security: Biometric authentication, Keychain Storage, Mobile App Developer tools for secure codebases. ✔️ Complex integrations (Stripe, Blockchain, Chat, Voice Assistants) built for modern mobile app infrastructures. 3. Fast delivery & agile process ✔️ We reduce time-to-market by 30–50% through optimized Mobile App Development pipelines, CI/CD (Fastlane, GitLab, Bitrise), and code reuse. ✔️ Agile-based teamwork (Scrum, Kanban) with TDD and thorough testing on real devices for bulletproof mobile releases. ✔️ Our Mobile App Developers excel in dynamic feature delivery, updates via App Store Connect & Play Console. 4. UI/UX That Converts in Mobile ✔️ Intuitive, inclusive design via Figma, Adobe XD, Sketch – essential in every Mobile App Development stage. ✔️ WCAG-compliant interfaces, A/B testing, user retention optimization = happy users. ✔️ We deliver interfaces your customers love – thanks to experienced Mobile App Developers who care about user experience. 📲 Industries we’ve powered with Mobile App Development: ✔️ Fintech, Health & Wellness, Meditation, Beauty, Fitness, Telemedicine, Logistics, Shopping, Hotel & Restaurant, Audio/Streaming, E-commerce, Real Estate, Social & Messaging, Mobile Games, Blockchain, NFTs ✔️ Our Mobile App Developers understand industry-specific challenges and offer smart, scalable mobile solutions using best practices in Mobile App Development. 🔧 We handle all aspects of Mobile App Development: security, performance tuning, testing (TestFlight, emulators), version control (GitHub, GitLab), and project tracking (Slack, Asana). ⏳ Let’s talk about your Mobile App Development needs. Our Mobile App Developers are ready to jump in. First consultation – free! 📩 Message us now and see how great Mobile App Development can be when done right.
    Featured Skill Kotlin
    watchOS
    Mobile App Bug Fix
    SwiftUI
    Mobile App
    Android SDK
    Native App Development
    iOS SDK
    AI App Development
    iOS Development
    Android App Development
    Mobile App Development
    iOS
    Android
    Swift
  • $30 hourly
    • 5.0/5
    • (8 jobs)
    👋 Greetings! With over 1️⃣5️⃣ years of extensive experience in iOS and Android Mobile App Development, I bring a unique blend of design, development, and technical leadership to every project. 🎓 M.S. in Computer Programming, with expertise across multiple development stacks. ⭐️ Hundreds of 5-star reviews! 🎯 100% Job Success on platforms like Upwork and beyond! 🚀 I am a full-cycle mobile developer, taking your project from an initial 💡 idea to a fully functional 📱 mobile application. I handle everything from UI/UX design to backend API integration, ensuring a seamless experience from start to finish. Whether it’s native iOS development with SwiftUI or Android development using Kotlin or Java, I am here to build high-quality apps. 👉 Contact me today for a free project consultation, and let’s discuss how we can bring your mobile app vision to life! Technologies and Tools: ✅ Native iOS Development: Swift, SwiftUI, Objective-C, Core Data, Core Animation, XCTest ✅ Native Android Development: Java, Kotlin, Jetpack Compose, Room Database, Retrofit, Dagger, Coroutines ✅ Cross-Platform Development: Flutter, React Native, leveraging Dart and JavaScript for hybrid mobile apps. ✅ Backend Integration: Firebase, REST APIs, GraphQL, Node.js, Python, AWS, Azure, Google Cloud ✅ Databases: MySQL, PostgreSQL, MongoDB, Redis, Cassandra, Firestore, SQLite ✅ Version Control: GitHub, GitLab, Bitbucket, SVN ✅ CI/CD Tools: Jenkins, GitHub Actions, GitLab CI, CircleCI, Bitbucket Pipelines, Docker, Kubernetes ✅ Testing & Automation: TDD, BDD, Unit Testing, XCTest, Espresso, Selenium, Appium, JUnit ✅ Cloud Services: AWS Lambda, Azure Functions, Google Firebase, AWS EC2, S3, DynamoDB, CloudFront, CloudFormation ✅ DevOps: Kubernetes, Docker, Terraform, Ansible, Puppet, Chef, Jenkins, CircleCI ✅ API Development & Integration: RESTful APIs, GraphQL, OAuth, OpenID Connect, Third-Party SDK integration ✅ Payment Gateway Integration: Stripe, PayPal, Braintree, Razorpay, Apple Pay, Google Pay Areas of Expertise: 💪 I specialize in creating scalable mobile apps with microservices architecture and event-driven designs that can handle high traffic and scale seamlessly. My focus on app optimization ensures that both iOS and Android apps run efficiently, providing users with the best experience possible. Featured App Development Projects: 📦 Food and Retail Delivery Platforms: Fully customized solutions for drivers, staff, and customers, including real-time tracking, push notifications, and in-app payments. 👥 Social Media Apps: Building feature-rich platforms with chat, feeds, profiles, push notifications, user authentication, and real-time updates. 🔄 E-commerce and Marketplace Solutions: Complex buy/sell platforms with secure payment gateways, commission structures, inventory management, and smooth customer experiences on mobile. 📊 Productivity Apps: Designing and developing task management and expense management apps for cross-platform use, utilizing Flutter and React Native for seamless integration across devices. 🌟 I turn ideas into high-performing, market-ready mobile apps with a keen eye on user experience and performance optimization. Whether you need a native iOS app or a cross-platform solution with Flutter or React Native, I’m here to help. Let’s collaborate to make your app the next big thing on the Apple App Store and Google Play Store! ⚡️ Updated portfolio: February 28, 2025
    Featured Skill Kotlin
    User Authentication
    User Profile Creation
    Tablet
    Smartphone
    JavaScript
    Mobile App Development
    Android
    iOS
    Flutter
    iOS Development
    React Native
    Xamarin
    Swift
    Android App Development
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