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Rating is 4.8 out of 5.
4.8/5
based on 7,380 client reviews
  2. Development & IT Talent
  3. Mobile App Developers
  4. (Current) Kotlin Developers
  • $10 hourly

    • 4.9/5
    • (8 jobs)
    ⭐ If you’re looking for an excellent web and mobile app developer, you’ve come to the right place! ⭐ I will transform your ideas into incredible apps and websites by using the latest technologies to efficiently build first-rate web and mobile apps. I am passionate about developing responsive and complex websites and mobile apps, crafted to meet your needs. I will make sure your web and/or mobile app is scalable and can be adapted to new market demands in the future. Plus, as server-side development expert, I’ve got you covered there as well! ★ 15+ years of experience in app and website development ★ 💪🏼 My area of expertise are: Frontend: Java, Kotlin, Swift, SwiftUI, Objective C Cross-platform: React Native, Flutter, Ionic Framework IDE: Android Studio / Xcode / Eclipse Web: ReactJS, Ruby, AngularJS, Node JS, Ember JS, MEAN, MERN, HTML5, CSS, jQuery Backend- PHP, Python, Laravel, Django, NodeJS, ExpressJS Database- MongoDB, Firebase, PostgreSQL, MySQL, Relational ✩ Hands-on experience with Core Frameworks of Android/iPhone SDK and 3rd party SDKs and APIs, Push Notifications, Payment Gateways, Analytics, Ads ✩ Well-versed with UI layout designing and UX fundamentals ✩ Understanding of MVC/MVVM patterns, experience with Agile/Scrum Development Methodology and Git Operations ✩ Available 24/7 for communication ✅ These are the domains in which, I have developed apps and websites: Food delivery, On-demand services, Salon and Beauty, Taxi booking, Car rental, E-commerce, Health and fitness, Travel, Music streaming, Video streaming, Fintech, Telemedicine, Real estate, Social media, Dating, Online education, Hotel & Flight Booking, Online grocery ordering and many more ✅ I follow the following steps to build a cost-effective product that meets your requirements and market demands. [ The Vision ] Successful products are never made alone. I work as one team with my clients to proudly create products that people will love. [ Strategy & Discovery ] No successful product is created without proper research. I dig into both the competitive and the technological landscape to make sure that your app and website is cutting-edge on every front. [ Achieving Unforgettable Design ] I design user journeys and wireframes to develop an unrivaled view of the user experience. When a seamless UX intersects with a richly designed UI, there I win. [ Development & Testing ] With full-stack development expertise, I continuously test throughout the development phase of the project to ensure that only the highest quality is delivered for your final product. [ Building For Growth ] Once your app launches, it’s not over. I am here to support your app post-release with maintenance and improvement so that the number of happy users continues to grow. I welcome the opportunity to hear your idea and convert it in to an amazing app or website that people will love.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Web Development
    Python
    React Native
    Stripe
    Django
    Laravel
    PHP
    WordPress
    Shopify
    Ecommerce
    Geolocation
    Swift
    App Development
    API Integration
  • $40 hourly

    • 4.9/5
    • (26 jobs)
    🌟 Top-Rated Upwork Professional 🧑🏻‍💻 9+ years of experience 📱 Android | Kotlin | Java | Jetpack Compose | Kotlin-Multiplatform| Flutter | WearOS | AndroidTV | 🚀 AI | ChatGPT | 💻 Firebase | VoIP | Linphone With over 9 years of extensive experience as an Android Developer, I specialize in native Android application programming with a strong focus on SCRUM/Agile workflow. 
 
I have a proven track record of delivering high-quality mobile applications in various domains, including:
 * Airline Domain * Banking Domain * Cargo Management Domain * Logistics Domain * Financial Domain * Social Media/Dating Domain with Video/Audio Chats * Location Tracking Domain
 My expertise in mobile development includes:
 * Programming Languages: Java, Kotlin * Architectural Patterns: MVVM, MVP, MVC * Design Patterns, Custom Controls, and REST API integration * Material Design, Mobile UI/UX, and Firebase integration (AdMob, Analytics, A/B testing, etc.) * Jetpack Compose, Jetpack Navigation * Firebase Realtime Database and Storage * Android SDK, NDK, Open Source, Support Libraries * Reactive Programming with rxJava and rxAndroid * Dependency Injection using Dagger, Kodein, and Hilt * Databases: SQLite, Room, Realm, Page * Network Libraries: Retrofit, OkHttp, Volley, ktor * Image Loading Libraries: Picasso, Glide * Crash Reporting and Analytics Tools: Crashlytics, Firebase, Fabric, LeakCanary, Timber * Other Libraries: Gson, AutoValue, JodaTime, AndroidJob, Google Services * Sockets/SignalR * Kiosk Mode * SonarQube code coverage * Kotlin-Multiplatform (One POC)
 * Wear OS & Smartwatch development In addition, I am an expert in the Linphone SDK, a powerful tool for building voice and video communication applications. I have in-depth knowledge of integrating and customising the Linphone SDK to create high-quality, real-time voice and video chat functionalities within Android applications. I am experienced in implementing Linphone's advanced features, including call management, audio/video codecs, encryption, push notifications, and more. Whether you need to develop a VoIP application from scratch or enhance an existing app with Linphone capabilities, I can provide the expertise you require.
 I have integrated various features and technologies into Android applications, including:
 * Beacons integration for proximity-based interactions * Calendar API integration for managing events and schedules * QR Code integration for scanning and processing QR codes * OCR (Optical Character Recognition) integration for text recognition and extraction
 For multimedia capabilities, I have integrated Video Chat using WebRTC, Twilio, and Agora, as well as Audio Streaming. I am familiar with ExoPlayer for HLS Video Streaming (HTTP Video Streaming), RTSP Video Streaming, and DASH Video Streaming.
 Other skills and features I offer include Custom Calendar development, Media Gallery implementation, Background Download and Upload functionality, Tiff file format handling in Android, Live Streaming using Agora SDK, Deep Linking, LeakCanary for memory leak detection, and code annotations to improve the linting process.
 Experienced Kotlin Multiplatform Developer with a track record of delivering efficient cross-platform solutions. Proficient in Kotlin Multiplatform Mobile (KMM) and skilled in creating high-performance apps for Android, iOS, web, and more. Experienced Jetpack Compose Developer, proficient in creating dynamic, interactive, and modern Android UIs. Skilled in leveraging Jetpack Compose's power to build visually stunning and responsive applications. - Experience migrating target api level 33 - Update existing app I am fluent in English and passionate about Android development. Please feel free to reach out to me with any Android-related questions or projects. I would be pleased to help you bring your ideas to life.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    User Profile Creation
    User Authentication
    Payment Functionality
    Social Media Account Integration
    Wear OS
    In-App Purchases
    VoIP
    NFC
    Firebase
    Firebase Realtime Database
    Push Notifications
    API Integration
    Bluetooth
    Android
    Map Integration
    Java
    Android App Development
    Location-Based Service
  • $60 hourly

    • 5.0/5
    • (7 jobs)
    💻 I've been creating software for Android OS since 2017. 🚀 Developed over 30+ projects for millions of users. 🌎 Have experience with international teams and customers from Great Britain, the Republic of Zimbabwe, the USA, Russia, Ukraine, Romania and others. Can help you: 🔹Create an Android application from scratch 🔹Optimise your existing android application 🔹Choose the most reliable and convenient technology stack and architecture for your application 🔹Provide quality estimation of a task 🔹Find and resolve issues of your android application and implement new features 🔹Interview candidates on Android developer position into your team 🔹Grow your business via high-quality application I have experience in projects: 🔸E-commerce, social, communication projects 🔸Internet banking applications 🔸Telecommunications 🔸Cryptocurrency 🔸Media player 🔸Device hardware (Bluetooth, GPS, Accelerometer, Camera, etc.) 👋Do not hesitate to contact me If you need any further information 👋
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Model View Presenter
    Model View ViewModel
    RxJava
    Dagger 2
    Android Room Persistence
    Firebase
    Agile Software Development
    Multithreaded Programming
    Material Design
    Android App Development
    solidThinking Envision
    Clean Architecture
    Android SDK
    Java
  • $63 hourly

    • 4.9/5
    • (56 jobs)
    Ever felt swamped in the vast sea of mobile app developers? It's frustrating when deliveries are late, functionalities go missing, and codes resemble intricate mazes. Trust me, you aren't the only one navigating these waters. Many collaborators have shared stories of past stumbles. But here's a ray of hope: we can steer towards a brighter horizon. With a decade under my belt and a heart full of passion, I aim to rewrite these narratives. Some Milestones: ⭐ Spearheaded development for Fitbit, which impressively raised $66M. ⭐ Had the honor of collaborating with Pure, Powerdot, and Xsat, all of which celebrated significant investment milestones. ⭐ Steered numerous projects using cutting-edge technologies, simplifying and accelerating the development trajectory. ⭐ Seamlessly merged the principles of Agile & Scrum, fostering flexibility and quick turnarounds. Let me introduce myself I'm Sergey, possibly your next Lead Android/iOS Developer. The past decade has been an exhilarating roller-coaster, packed with invaluable experiences, challenges, and a string of successful projects. I've lent my expertise to startups, and industry giants, helping them manifest their mobile app dreams. Why do they choose me? ✅ A relentless drive to craft projects that stand out and garner rave reviews. ✅ Undying support post-project because our relationship isn't just transactional. ✅ A rich toolkit encompassing Kotlin, Swift, and trailblazing frameworks like Jetpack Compose & SwiftUI. ✅ Agility in approach with a deep-rooted foundation in OOP & Functional programming styles. My Array of Specialties: 📱 Leading mobile development with Kotlin, Java, Swift 🚀 Cross-platform mobile app development using Flutter, React Native 🌐 Backend prowess with Firebase and Node.js. 💻 Architectural excellence with MVVM, MVP, MVI, and VIPER. 🔄 Transparent updates and effortless communication, ensuring you're always in the loop. In a nutshell? I value transparency, efficiency, and making a tangible difference. It's not just about crafting any mobile app, but sculpting one that resonates, scales, and surpasses the norm. Ready to embark on an extraordinary journey? Let's unite over a virtual coffee and set the wheels in motion for your next mobile marvel!
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Machine Learning
    VPN
    Wear OS
    Smartphone
    Mobile App
    iOS
    Android
    iPad App Development
    Android NDK
    Java
    Android App Development
    Android SDK
    Swift
    iOS Development
  • $35 hourly

    • 4.8/5
    • (39 jobs)
    I am a Mobile developer with more than 4 years of experience and lots of successful projects behind. ♨ Technologies: ✔ Java(4 years) / Kotlin(2 years); ✔ Git; ✔ Android SDK/NDK; ✔ Android Jetpack (WorkManager, Room, Navigation, Lifecycle); ✔ Firebase (Analytics, Authentication, Cloud Firestore, Cloud Functions, Cloud Messaging, Cloud Storage, Crashlytics, Performance, Realtime Database, Remote Config); ✔ Gradle (Groovy and Kotlin DSL); ✔ RxJava, Kotlin Coroutines; ✔ Hilt, Dagger 2, Toothpick; ✔ SQLite, Room, Realm; ✔ Google APIs (Maps, Drive, Tasks, Places); ✔ ExoPlayer (DASH, SmoothStreaming); ✔ Glide; ✔ REST/JSON/XML ✔ Retrofit 2; ✔ Proguard, R8; ✔ Lint, Ktlint, CheckStyle; ✔ Crashlytics, Instabug, Leakcanary; ✔ Junit, Mockito, Espresso; ✔ MVVM, MVP, Clean Architecture; ✔ Facebook, Google, Linkedin, Twitter, and other social applications auth communication; ✔ 3rd party libs integrations. Thank you in advance for your time and consideration.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Tablet
    Android
    Flutter
    React Native
    CSS
    HTML
    Mobile UI Design
    SQL
    Android SDK
    Android App Development
    Java
  • $60 hourly

    • 4.9/5
    • (186 jobs)
    ** I am what I am because of what we all are. ** I am a self-motivated, hard-working, and open-source contributor. My GitHub handle is *amsurana* Mobile experience [since 2009] * Worked on Qualcomm, Mediatek, Amlogic, Rockchip based devices. * Porting and Writing Device Drivers * Customizing Android Kernel * Android Automotive OS Expert - Projects and Consulting. Ported Automotive OS to RPI. * Android Firmware development for all kind of Devices [PCBA, Phones, Tablet, TV, Accessories] * Android SDK/NDK * Android Wearable * Custom ROM - I have deep experience in customizing Android and modifying the entire OS experience as per the requirements. Some of the customizations I have done - changing boot animations, modifying shutdown screen, removing bloatware, developing system-level apps, making a tablet a Kiosk (without permissions), Bluetooth stack modification, Carrier config updates, and many more. * Secure OS - Make your Android ultra-secure. * OTA for A/B Seamless or Non-AB devices * Secure Android OS using AVB Tool * MDM, EMM, Mobile Device Management - If you plan to use MDM or develop your MDM, do reach out to me. I have experience in Airwatch, SOTI, ScaleFusion, Gears42, and FieldX. Special Skills: Z-wave, Zigbee, IoT, Amazon Alexa, Google Home Assistant, Smarthome, IFTTT Keywords - Android, Web, Social Media Integration, Java, J2EE, Bluetooth, BlueZ, DBus, AOSP, Custom ROM, Docker, Play Framework, Linux, AWS, EC2, MongoDB, Eclipse, Cyanogen mod, LineageOS Android TV, Android OS, Custom ROM, Tizen, LinegaeOS, RaspberryPi, OrangePi, Khadas VIM, HiKey, Amlogic, Rockchip, Airwatch, SOTI, MDM, EMM, Pentest, Penetration Testing, Qualcomm, Mediatek
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Raspberry Pi
    Mobile App Development
    Android SDK
    Embedded System
    Internet of Things
    Firmware Programming
    Firmware
    Mobile Device Management
    Android NDK
    Android App Development
    Android
    Java
    AOSP
  • $20 hourly

    • 4.9/5
    • (9 jobs)
    I am an Android Developer with 3 years of experience. Have strong knowledge of Android SDK and Android ecosystem. Can deliver numerous functionality into your application. • Java SE, Kotlin • Android SDK • Android Architecture Components • RxJava 2 • Integrating RESTful Api • JSON, XML • OkHttp3 + Retrofit2 + Gson • Google Play Services • In-App purchases • Google Maps, GPS • ExoPlayer • AdMob Also, I am well acquainted with: OOP/OOD, SOLID, collections, multithreading, design patterns, Material Design principles, MVC, MVP, MVVM and Clean Architecture. I am always open to new interesting and challenging projects and ready to build the best quality products!
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Mobile App Development
    Google Maps API
    Firebase
    Tablet
    In-App Purchases
    Smartphone
    Android Studio
    SQLite Programming
    Mobile UI Design
    REST
    Git
    Java
    Android
    Android App Development
  • $35 hourly

    • 4.8/5
    • (6 jobs)
    Hello there! If you’re looking for a reliable Senior Android developer, you are on the right page. I'm a seasoned Android developer, crafting reliable, fast, and top-notch apps. Global projects across varied domains have honed my skills and enriched my tech arsenal. 🛠 Key skills: 📎 Kotlin & Java: My trusty languages. 📎 Android SDK & Jetpack: Foundation of my work. 📎 SQL, Rxjava, Retrofit2: Tools for data and communication. 📎 Firebase & Git: Ensuring smooth workflow. 📎 MVVM, MVP: My guide for structuring apps. 📎 Design Patterns, In-app Billing, Google Maps: Enhancing user experience. 🤝 I value clear, SMART communication and deadlines, making teamwork a breeze. Ready to dive into new challenges and eager to learn, so drop me a line with your requirements. Let's create digital wonders! 📲 _____________________ * Need a wider range of services? No worries, you are on the right path anyway. I'm working in association with the 90-person-strong TOP Rated Plus Agency - PECODE. You can count on us if you need experts in UX/UI design, Mobile app development, Quality Assurance ( manual & automation). We will support you at each stage of development: 🥇 Before the start we provide you estimates based on project requirements analysis and specification 🥇 Take care of the web product's development from needs to production 🥇 Support and improve the product after realise. Since 2017 we bring client's ideas into reality, and we are looking forward to starting the collaboration with you!
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Google Play
    Android SDK
    Git
    RxJava
    Dagger 2
    Native App Development
    API Integration
    Map Integration
    Smartphone
    Tablet
    Location-Based Service
    Android App Development
    Java
    User Authentication
  • $25 hourly

    • 4.9/5
    • (29 jobs)
    Full Stack Developer with 19+ years of experience. Developed modules/applications in .Net and Java frameworks for both large scale enterprise products and medium scale web applications. Skill Set ✔ Front-end: MAUI, .Net Blazor, Vue js, React.Adobe Flex ✔ Back-end: .Net, Java, Kotlin, Spring Boot, ✔ Databases: MySQL, SQL Server, PostgreSQL, Mongo, Redis ✔ Dev-ops: Git,. Dockers, CircleCI, AWS, Azure ✔ Scrum: Atlassian Jira, Confluence,
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Vuetify
    PostgreSQL
    Adobe Flex
    AWS Amplify
    Azure
    React
    Vue.js
    Spring Boot
    Java
  • $155 hourly

    • 4.7/5
    • (25 jobs)
    **EXPERT VETTED BY UPWORK** Top 1% in Mobile App development, Web development and Blockchain development I lead a small talented team of software engineers and designers. So instead of getting one expert on your team, you will always get a team of experts. Executing greenfield projects is something that we enjoy! I guarantee you: My team will provide the best value that you can find. Why work with me: - My DC-based company OakTreeApps.com is a blockchain-first dev shop using bleeding edge tech stack. - Have successfully launched apps in the marketplace for platforms such as Wellbility & EchoLokal. - Have successfully launched projects in crypto space: KandiKids (kandikids.io/), CosmicUniverse (cosmicuniverse.one/) - Have served as Director of App Development within an upcoming healthcare tech startup. - Mentor at Polygence We are a team with decades of experience working on: || DApps || NFT Marketplace || Social Money 1. Enterprise grade apps 2. Social media apps 3. Multimedia consumption apps 4. Connected car apps 5. Healthcare apps 6. Hyperlocal apps Web 3.0 framework we use: || Solidity, Truffle, Metamask, OpenZeppelin || Web 2.0 tools we use: 1. Kotlin/Java 2. RxJava/RxAndroid 3. Dagger2 4. ViewModel/Databinding 5. Objective-C/Swift 6. RxSwift 7. MVVM/Clean code architecture 8. Laravel/Vue.JS + MySQL/Mongo 9. Flutter/Dart for cross-platform development 10. Cocoapods/YAML/Gradle 11. CI/CD using Jenkins/CircleCI 12. Audio, Video streaming using AVKit/ExoPlayer, etc. 13. APNS/Firebase push notifications/Urban Airship 14. Picasso/Glide/Kingfisher 15. Payment integration using Stripe/PayPal etc. 16. AWS EC2/Amplify/Route 53 17. Firebase using push notification, realtime database, phoneauth & much more! We understand that finding the right candidate for the job can be tedious and stressful. That's why when you choose to work with us, we shall make things as simple and easy as possible, striving hard to provide you with a 100% stress-free experience. Let's have a chat about your product needs, and let us help you grow your business. Thank you!
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    React
    Node.js
    Swift
    Apple Xcode
    Android
    MongoDB
    Ethereum
    Vue.js
    Blockchain Development
    Blockchain
    Smart Contract
    Flutter
    AWS Server Migration
  • $40 hourly

    • 4.9/5
    • (50 jobs)
    Android Developer from Ukraine (UTC+2), with 10+ years of experience in designing and implementing Android applications. Deep expertise in Kotlin and Java for Android and Material Design Guidelines, skilled in mobile UI development, experienced with version controls such as Git, have great analytical and problem-solving skills. Android Jetpack; AndroidX; MVVM; MVP; MVI; MVC; Android Jetpack; AndroidX; MVVM; MVP; MVI; MVC; Company HR - please do not disturb.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Tablet
    Model View ViewModel
    Retrofit
    Android Room Persistence
    Firebase
    Native App Development
    Android SDK
    Android
    Gradle
    Git
    SQL
    Java
    JSON
    Android App Development
  • $55 hourly

    • 5.0/5
    • (28 jobs)
    I have been freelancing for two years, and have a 100% client satisfaction rate over a variety of complex projects. My speciality is MIDI and audio with native code, but I am also adept at generic Android client work, and can churn out screens at an impressive rate! I have written the most fully featured and music notation app for Android singlehandedly, as well as Forex trading tools, a Midi to MP3 converter, a band management system, forum browsing software and a discussion game for a charity. I have 14 years commercial experience in C/Linux. I adhere to sound software design principals (SOLID, TDD, Clean Architecture). I can learn any new framework extremely quickly, and am up-to-date with the latest Android components and patterns (Jetpack, MVVM, MVI).
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Mobile App Development
    Tablet
    Native App Development
    Android SDK
    Android Studio
    Android Room Persistence
    Android App Development
    Android
  • $15 hourly

    • 5.0/5
    • (2 jobs)
    Computer science student with practical experience using Android Studio through internship. Enjoys developing Android apps and designing them. Willing to try the hardest and learn new skills to achieve the desired work.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Mobile App Development
    Golang
    PostgreSQL
    Java
    Android Studio
    Android App Development
    Android
    User Authentication
    Firebase
    SQLite
    MySQL
  • $10 hourly

    • 5.0/5
    • (11 jobs)
    As an enthusiastic and dedicated Android developer, I take pride in crafting innovative and user-friendly mobile applications. With a passion for creating seamless digital experiences, I have honed my skills in Java and Kotlin, harnessing the power of the Android SDK to bring ideas to life. My journey as an Android developer has equipped me with a diverse set of skills, enabling me to tackle various challenges that come my way. Whether it's developing a feature-rich app from scratch or optimizing existing code for peak performance, I always strive for excellence in every aspect of my work. I firmly believe that effective communication and collaboration are key to delivering successful projects. Throughout my career, I've had the pleasure of working with clients from diverse backgrounds, understanding their unique requirements, and translating them into scalable solutions that exceed expectations. My focus on staying up-to-date with the latest industry trends and best practices ensures that I can deliver cutting-edge Android applications that stand out in today's competitive market. I'm not just a developer; I'm a problem solver and a reliable partner in your app development journey. Let's work together to turn your ideas into reality and create Android applications that leave a lasting impact on your users. If you're looking for a skilled Android developer who is passionate about innovation, quality, and client satisfaction, feel free to reach out. I'm excited to be a part of your next project and contribute to your success. Let's build something incredible together!
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    RxJava
    Mixpanel
    Core Java
    Database Programming
    Web Service
    Payment Gateway Integration
    Android
    Android App Development
    Firebase
    Mobile App Development
    Business with 1-9 Employees
  • $10 hourly

    • 5.0/5
    • (3 jobs)
    I am Java/Kotlin android developer with 2 years of experience. I can make a solid and maintainable android application with clean architecture principles and modern technology stack. Jetpack Compose, Dagger/Hilt, Kotlin Coroutines, etc.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Unit Testing
    Android Room Persistence
    Retrofit
    Coroutine
    Dagger
    Model View Intent
    Model View ViewModel
    Clean Architecture
    Google Play
    Android App
    Android App Development
    Android SDK
    Android
    Java
  • $23 hourly

    • 4.9/5
    • (48 jobs)
    Greetings! I am a highly experienced and top-rated mobile developer with over 14,000 working hours on Upwork. My expertise lies in developing native iOS and Android apps, as well as cross-platform apps using React Native and Flutter. Over the years, I have worked on a wide range of projects, from simple utility apps to complex enterprise-level solutions. My skills include: • Strong knowledge of Swift, Objective-C, Java, Kotlin, React Native, and Flutter • Experience working with various APIs and SDKs, including Firebase, Google Maps, and AWS • Proficiency in using version control systems such as Git and SVN • Ability to design scalable, maintainable, and reusable code • Strong debugging and troubleshooting skills • Familiarity with Agile methodologies In addition to my technical skills, I am also an excellent communicator and team player. I have worked with clients from various industries, and I understand the importance of clear communication, timely delivery, and excellent customer service. If you're looking for a reliable and skilled mobile developer, I am here to help. Feel free to get in touch to discuss your project requirements in detail. Thank you for your time, and I look forward to working with you! Best regards, Oleksii .
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    iOS SDK
    React Native
    Flutter
    In-App Purchases
    Java
    Objective-C
    Android App Development
    iOS Development
    Swift
    SwiftUI
    Smartphone
    Mobile App Development
    Android
    iOS
  • $30 hourly

    • 5.0/5
    • (31 jobs)
    I am an expert in creating Native Android and iOS apps. I follow modern software development practices. I write high-quality Android apps by following standard practices so my apps always have the best performance and present a smooth user experience. If you have an app idea and want to turn it into reality or you already have an app and you want to improve it, I can help you with that. I am listing my skills below for you. Programming Languages and Frameworks • Java • Kotlin • Swift • SwiftUI • RxJava • RxKotlin • Android NDK • SceneForm(Framework to add AR in your app) Android Jetpack Components • ViewModel • LiveData • Room(Sqlite) • JUnit • Mockito • Navigation Components Dependency Injection • Dagger • Kodein Databases: • Room(Sqlite) • Firebase (Realtime database, notifications, Crashlytics…etc) • MongoDB Realm • MySql • Core Data Software Development Tools: • Version control (git) • Continuous Integration • Slack • Trello Other than that I have experience with APIs like Twilio, Sinch, Agora, Facebook, Twitter etc. I also have experience with Android Bluetooth. I can build apps that can communicate with devices like household items through Bluetooth. These are just a few of the skills I have experience with. Please contact me if you're interested and I'll help you build the next big thing like Airbnb, Snapchat etc.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Apple Xcode
    RxJava
    C++
    SQL
    Android SDK
    Android App Development
    Swift
    Java
  • $80 hourly

    • 4.8/5
    • (43 jobs)
    If you are looking to develop functional Android Apps, effective design or performance, you've landed exactly at the right place. I know how to make your customers happy and make you more sales. I take on a limited number of projects at one time. This quality control means I can give each one exactly what it needs –­ focus and time. Customer satisfaction is my first priority and I always go the extra mile. I always put myself not only in my client’s shoes but also in the shoes of the end-user. Every project has its target audience with its own needs, expectations, taste, etc. I use empathic design and techniques throughout my process in order to reveal the values and aspirations of users. Now let me tell you about my Strengths and skills: -Complete MVP architecture with Dagger 2 and RxAndroid implemented apps. -Firebase tools(push notification, dynamic linking, analytics, Crashlytics, Non-SQL realtime db, cloud functions etc). -API based Apps(using retrofit, volley, can develop APIS also in Laravel and CodeIgniter, Slim). -Amazon tools(EC2, API Gateway, S3 Buckets, Lambda functions, push notifications, RDs and RedShift). -Google Apis(auth, google+, voice recognition, image recognition, text processing, machine learning etc). -Dropbox Apis(storage APIs). -Twitter, LinkedIn, Facebook Apis(auths, Facebook analytics and crash reporting). -All other useful application tools(background services, system-level communications, file storages based, notifications, offline apps, communication apps, wallpaper apps, system tracking apps, etc) Development tools always concern a lot for clients sometimes. I have a great experience in these professional tools and techniques -Project Management Tools i.e Jira, trello etc -Version control system bitbucket, GitHub etc. -Skyp for business -Android studio -Eclipse -Intelij IDE -Postman Sounds Good! I would love to work with long-term clients and make a good long-term working relationship. I will ensure the overall budget will be acceptable for you and for your team and maintenance Cost would be so much less so that you can easily break through all the hurdles in leading a successful android Product.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    In-App Purchases
    Map Integration
    PHP
    Flutter
    Push Notifications
    Camera
    ARCore
    OpenCV
    Machine Learning
    Android NDK
    Android SDK
    Android Studio
    Android App Development
    Android
  • $40 hourly

    • 5.0/5
    • (29 jobs)
    Hello I am a senior Full Stack mobile app developer with 6 years coding experiences of Swift, Kotlin, Objective C Java, JavaScript and Php. In the last years, I have built several kinds of mobile apps with Native & Hybrid(React Native) frameworks so that i can provide good suggestions for your project and high quality result. What kind of mobile app are you going to build? with Native or Hybrid? You can build amazing perfect app with me base on your choice. I am always ready for you and hope to build good partnership with you. Regards
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Web Development
    Ruby on Rails
    ASP.NET
    .NET Framework
    Ruby
    iOS Development
    Java
    Android App Development
    C#
    Swift
    Objective-C
    Mobile App Development
    iOS
    React Native
  • $60 hourly

    • 5.0/5
    • (9 jobs)
    Fundamentals: Experienced Android Developer 20+ released projects 7+ years of Android development experience English: Fluent I've been developing high-quality mobile apps for more than 7 years now. I've been working on a broad variety of projects: mobile banking apps, mobile clients for enterprise systems, educational and entertaining apps, b2b and b2c projects. I've worked with applications requiring different technologies and skills. I especially want to note the experience of fixing errors made by previous developers.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    In-App Purchases
    Mobile App Development
    GraphQL
    SQLite
    Android NDK
    Google Maps API
    Mobile UI Design
    Android App Development
    Firebase
    Websockets
    Material Design
    Android SDK
    Java
    REST
  • $30 hourly

    • 4.9/5
    • (9 jobs)
    I am Osemwingie Oshodin, I am a value driven mobile engineer. I am proficient in Kotlin, Kotlin multiplatform, android architecture, Jetpack libraries, backend development using Ktor, and building cross-platform applications using Flutter I have successfully deployed multiple mobile applications built from scratch to the google play store. I have also contributed to many projects by working in a team. I have gone on to further my skills in software engineering by taking relevant courses and acquiring a google associate developer certificate. 
I am excited about learning new technologies. My utmost priority is to satisfy my clients by delivering optimal products that satisfy the expectation of the end-users. In my free time, I like to watch sports and listen to music.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    JetPack
    Model View ViewModel
    Flutter
    Java
    Android App Development
    Android
  • $20 hourly

    • 5.0/5
    • (15 jobs)
    #Android #Dev #Kotlin #Java #Firebase #MVVM #Livedata #MVP #Android Studio ♛ 100% Client Satisfaction. ✅ 8+ years of experience as an Full Stack Developer. ✅ 8000+ Hours of work history as an Full Stack Developer ✅ Master's degree in Information Technology. Hi, I describe myself as a Senior Android Application Developer with experience of 7 years. I am a responsible developer. I do my work with the full dedication and strive for excellent quality. Over the period, I have worked on various projects and managed them as a Team lead in Android, PhoneGap and web technology. I have expertise in executing applications for Android platforms using Native approach. My Skills: ✅ Android apps using Android Studio ✅ XML/JSON parsing, soap response and web service ✅ In app purchase, Paypal, Braintree, Stripe, CCAvenue payment integration ✅ Firebase and google cloud ✅ Chat & Messaging Engine: XMPP, Mqtt, PubSub ✅ Social Media (Facebook, Instagram, Google+, Twitter, Linkedin etc) Integration ✅ Geo Location, GPS, Google Map API ✅ Trello, Jira, Slack, Asana project management tool ✅ Google play store submission ✅ CI integration, Fastlane ✅ ARCore ✅ Text to speech ✅ Sensors, Bluetooth, Bluetooth LE ✅ Version control My Project Experience: ✅ API Integration app ✅ Firebase and Google cloud ✅ One signal SDK for send Push notification ✅ Social Networking app, Dating app ✅ Social Event and Messaging app ✅ Geo location app ✅ Food Delivery app ✅ Online ordering app ✅ Audio and video calling, video streaming app ✅ Scheduling app ✅ IOT based app Advantages : ✅ Every day reports about progress ✅ Well commented enterprise-ready source code ✅ Ultra fast response time I am seeking opportunities for an end to end development, maintenance, support, bug fixes and project management. I work full-time at Upwork and available online 16 hours in a day to answer any of your questions. Enthusiast to learn and adopt new things with a problem-solving mindset etc; For most of the project, I have signed NDA. Still, there are a few projects which you might like to have a look. Let's have a discussion about your new idea. Thank you for your time.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Smartphone
    Android
    Location-Based Service
    JavaScript
    Reactive Programming
    Android Room Persistence
    API Integration
    Java
    Android SDK
    Android Studio
    Android App Development
    Mobile App Development
  • $60 hourly

    • 5.0/5
    • (52 jobs)
    8+ years of experience working on native Android applications for high profile clients and businesses. I've strong Java/Kotlin programming skills including low-level performance optimizations and memory management. ✔ Ml-kit, OpenCv, TensorFlow, Camera, Image Processing ✔ Clean Architecture, MVVM, Firebase, Coroutines, Live data, DataBinding, Dagger2/Hilt, Room, Retrofit, Glide, Payments
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Android Studio
    Native App Development
    Firebase
    Java
    Android App Development
    Android
    Mobile App Development
    SQLite
    Camera Operation
    NFC
    Mobile App
    Android NDK
    Android SDK
    OpenCV
  • $25 hourly

    • 5.0/5
    • (10 jobs)
    I have more than 4 years of experience developing Android applications. I enjoy using and learning modern tech-stack and environments, estimating costs or developing time and providing valuable solutions. My main competences could be summarised as follows: • Android: Native Kotlin/Java (MVVM, LiveData, Coroutines, ViewBinding, Retrofit, Koin, Picasso, Dagger, Jetpack Compose) • Web Frontend: Bootstrap, JQuery, JS, CSS, JSF, PrimeFaces, RichFaces, JSP • Persistance: SQLite, Room, MySQL and NoSQL databases (GraphQL, MongoDB, Firebase Realtime Database) • Testing: JUnit // Mockk • Methodologies: Jira, Agile, SOLID Drop me a line!
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Android SDK
    Google Play
    HTML
    Model View ViewModel
    Android App Development
    Firebase
    Java
    Android
  • $75 hourly

    • 5.0/5
    • (26 jobs)
    I'm a Top Rated native Android developer (9+ years of experience) and a fluent English speaker. My strong point is in creating and maintaining complex Android apps from an idea to publishing in the stores. Skills and technologies which I'm an expert at: — Kotlin/Java — Android SDK, Android Studio — Git — MVP/MVVM/MVI — RxJava/Coroutines for asynchronous operations — Dagger2/Hilt for Dependency Injection — Retrofit/OkHttp for Rest API — Sqlite/Room for Database management — Firebase/Firestore: real-time database, authentication, notifications and crash reporting — OOP/SOLID/DRY I have 8k+ hours of work at Upwork and experience in a broad variety of apps, which I hope you'll find useful in your next project.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Android App
    Smartphone
    Android App Development
    Mobile App Development
    Gradle
    Android Studio
    SQL
    Git
    Android SDK
    English
    Dart
    Flutter
    Java
    Android
  • $50 hourly

    • 4.7/5
    • (39 jobs)
    Have experience developing complex mobile apps from scratch. Pro with Swift and Objective-C. Have implemented a wide variety of 3rd party APIs like Stripe, Firebase, Google maps, Twillio, etc. Work with Postman and many backend and database types. Skills: - Swift / Kotlin / React Native / Flutter - Native app development (iOS / Android) - Cross platform mobile development (iOS / Android) - Custom app development (iOS / Android) - App UX/UI design (iOS / Android) - App porting (iOS / Android) - App testing (iOS / Android) - Apps upgrade and maintenance (iOS / Android) Experience in apps development: - Startups Apps - Messaging Apps - Social Apps - Healthcare Apps - Delivery Apps - Booking Apps - E-Book Apps - Logistic Apps - Fin-Tech Apps iOS Tech-Stack: Xcode iOS stack Swift / Objective-C MVC / MVP / MVVM iOS SDK Twilio / Agora / Element Complex animations & responsive UI Cocoa Framework CocoaPods CocaTouch AVFoundation AVCaptureSession AVAudioSession Audio Unit AutoLayout Core Animations Core Audio Core Bluetooth Core Data Core Location Postgresql, MSsql Firebird / Interbase Firebase In-App Purchase Localization Storyboard JSON, REST API Push notifications Git (Github / Gitlab / Bitbucket) iBeacons / Bluetooth / IoT Mobile Apps Geolocation & Maps Android Tech-Stack: Android studio Java / Kotlin MVP / MVVM / Clean Android SDK Complex animations & responsive UI Coroutines 3rd party frameworks Twilio / Agora / Element Google Play Services Android Support Library Bluetooth Core Dagger 2 Kodein Glide Picasso Room JSON, REST API Push notifications Git (Github / Gitlab / Bitbucket) Firebase iBeacons / Bluetooth / IoT Mobile Apps Geolocation & Maps
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    SaaS
    CRM Development
    Mobile App
    Objective-C
    Stripe
    UX & UI
    Firebase
    Swift
    Mobile App Development
    Mobile Apps
    Android
    iOS
    Android App Development
    iOS Development
  • $40 hourly

    • 4.6/5
    • (64 jobs)
    My name is Adnan and I'm an Android and iOS developer. I speak and write English language at advanced level and I have around 7 years of experience in mobile app development especially with Android. I code Android apps in Android Studio with Java/Kotlin and I'm also familiar with iOS, Xcode with Swift/SwiftUI/Storyboards. In free time I'm learning about ML and Python and I hope in near future Machine Learning will be one of my next skills - Android Studio - Kotlin/Java - Retrofit, Volley, ButterKnife... - RxJava - MVVM - Xcode - Swift and some knowledge in Objective-C - SwiftUI - Alamofire, Kingfisher... Also: - Firebase (Authentication, Database, Firestore Storage), - Admob, Google Maps (current location, navigation etc), - Realm, Parse Experience with Jira and Git (Github, Bitbucket) I really enjoy delivernig a high quality code to my customers. I'm honest, funny and reliable person. Feel free to contact me! I look forward to hearing you.
    vsuc_fltilesrefresh_TrophyIcon Kotlin
    Logo Design
    JetPack
    Room
    Wearables Software
    Wear OS
    Apple Xcode
    iOS Development
    Swift
    Realm Database
    Firebase Cloud Firestore
    Firebase Realtime Database
    Android
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