Hire the best Kotlin Developers in New Jersey
Check out Kotlin Developers in New Jersey with the skills you need for your next job.
- $45 hourly
- 4.9/5
- (462 jobs)
For more than 10 years as a dedicated Professional Graphic Designer, my path has been illuminated by resounding endorsements and triumphant partnerships. I've engaged with 850+ individuals, corporations, and non-profit entities, weaving their imaginative aspirations into vibrant realities. My tailor-made creations have spanned an array of industries, etching bespoke solutions that resonate far and wide. 💎 Elevate Your Vision - USPs💎 🎨 Artistry Beyond Measure - A dynamic palette of over 7 years in crafting iconic brands, captivating web designs, and striking print visuals, infused with cutting-edge concepts and visionary creativity. 🌟 The Connection Catalyst - A virtuoso in interpersonal finesse, adeptly weaving collaboration and camaraderie. Your dreams and ideas find their perfect visual translator in me. ⏱️ Velocity Redefined - Embrace design at the speed of thought! Your concepts brought to life in a mere 24 hours, a testament to the fusion of precision and imagination. Experience design like never before. It's time to unveil the extraordinary. 💡🚀 Notable Clients: Linked In • Johnson & Johnson • Abbvie • Samsung • TATA • TED • Starbucks • Air Canada • City Bank • Siemens • Amazon • Bayer AG • Vale • FedEx • McDonald's • TAL Education Group • International Paper • LIC • IRCTC • Equinix Inc. • Marriott International • Biocon • Medtronic PLC • Terex Corporation • Thai Union Group and many more. Program Experience: Adobe Xd/Figma • Adobe Photoshop • Adobe Illustrator • Adobe InDesign • Adobe After Effects • Canva • Invision • Microsoft Office As technology evolves, I've also dived into AI areas like ChatGPT and MidJourney, providing services and training in these fields. My approach is elegantly simple: Craft with intention Work with a meticulous eye Forge a serene and efficient workflow and Cultivate enduring client connections. The outcome: a bespoke and harmonious visual tale that dances effortlessly across all horizons. ✨ Offering an extensive spectrum of graphic design solutions across various industries, my services encompass: • Distinctive Logo & Branding Design (Logos, Brand Boards, Business Cards, and more) • Dynamic Digital Marketing Graphics (Web Banners, Social Media Icons, GIFs, Advertisements, and more) • Compelling Infographics & Attention-Grabbing Marketing Materials • Engaging Print Media (Flyers, Posters, Brochures, and more) • Impeccable Layout Design (Annual Reports, Magazines, Menus, Ebook Formatting, and more) • Expressive Illustration (Children’s Books, Web Icons, T-Shirt Designs, and more) • Skillful Video Editing (Advertisements, Explainer Videos, Youtube Intros, Montages, and more) • Precise Photo Editing • Innovative Front-End Mobile Application & Web Design This comprehensive array of graphic design services caters to diverse industries, ensuring a tailored and detailed approach to meet your specific needs.Kotlin
Native FluencyAndroid SDKNode.jsJavaScriptTypeScriptReactAndroid App DevelopmentMobile App DevelopmentAndroidDartFirebaseFirebase Cloud FirestoreFirebase Realtime DatabaseFlutter - $200 hourly
- 5.0/5
- (74 jobs)
I have designed and completed many iOS/Swift, Unity/C#, React Native/Javascript, and Flutter/Dart-based apps as a sole, lead, or co-developer and published them on the Apple App Store and Google Play Stores. As a contractor for NASA, I published a Unity/C# iOS/Android augmented reality app for their Visitor Center in Goddard, Maryland, called "WeatherSats AR." I am currently working on multiple contracts in Native iOS, Android, and Unity. On the backend, my expertise is in Firebase, Firebase Functions, and now Microsoft Azure. I co-founded two iOS startup companies with other developers. One is a social media app for craft beer, and the other is a SwiftUI animation-based app where you can draw a multiple-choice question animation and share it with and challenge other users. I have a B.S. in computer science from Rutgers University in 2004, graduating with a 4.0 GPA.Kotlin
PostgreSQL ProgrammingJetPackiPad App DevelopmentAR & VRCocoa APIApple XcodeUnityFirebase Cloud FirestoreiOS DevelopmentSwiftObjective-CMobile App DevelopmentFirebaseC# - $75 hourly
- 4.5/5
- (36 jobs)
🏆 Top Rated Plus (Among the 1%) | 15 Years | 6000+ Hours Results-driven Project Management expert with extensive experience in Agile frameworks (Scrum, Kanban, LeSS) and a proven track record of leading multi-disciplinary teams to deliver high-impact software solutions. Certified Scrum Master, Advanced Scrum Master, and Scrum Product Owner with a deep understanding of project execution, process optimization, and cross-functional team collaboration. Skilled in managing large-scale web, software, mobile applications development as well as application migrations, infrastructure optimization, and ensuring alignment of IT strategy with business goals. Advanced proficiency in JIRA, Confluence, and other project management tools, with a commitment to fostering agile practices that enhance productivity, quality, and client satisfaction. CORE KNOWLEDGE & SKILLS ● Project & Program Management: Extensive experience in aligning technology projects with business goals, optimizing resource utilization, and ensuring project deliverables meet timelines and budgets. ● Agile Methodologies: Advanced in Agile practices, including Scrum, Kanban, and LeSS, with a focus on fostering a culture of continuous improvement. ● Technical Acumen: Skilled in JIRA, Confluence, MS Project, and Agile tools, with foundational knowledge of HTML, JavaScript, and SQL for cross-functional support. Let’s connect to discuss how I can contribute to your project’s success! Feel free to reach out via Upwork for more details.Kotlin
SwiftProgram ManagementProject ManagementProduct ManagementiOS DevelopmentASP.NET CoreDatabase DevelopmentWeb ApplicationReact NativeASP.NET MVCApp DevelopmentMinimum Viable ProductAPI DevelopmentSoftware Development - $65 hourly
- 4.8/5
- (27 jobs)
Welcome to my Upwork profile! I specialize in building high-quality native iOS and Android applications (Swift | Kotlin), as well as cross-platform solutions using React Native, Flutter, and other popular frameworks. My expertise extends to all aspects of mobile app development, including UI/UX design, API integration, performance optimization, testing, and deployment. My top priority is to deliver high quality work that meets my clients' specific needs and requirements. Whether you need a brand new app built from scratch or an existing app revamped and updated, I can provide the expertise and skills needed to get the job done on time and within budget. Some of the services I offer include: Native iOS and Android app development (Swift - 5 years, Kotlin - 5 years, Java - 5 years) Cross-platform app development with React Native, Flutter, etc. (Flutter - 3+ years) Custom UI/UX design and development Integration of third-party APIs and services Performance optimization and app scaling Testing and debugging Deployment to app stores and ongoing maintenance and support. If you're looking for a reliable and experienced mobile developer who can deliver high-quality work on time and on budget, look no further. Let's discuss your project and see how I can help bring your vision to live!Kotlin
GitJiraVersion ControlScrumKanban BoardAsanaGitLabLaravelGitHubReact NativeAndroidFlutterReactSwiftObjective-C - $40 hourly
- 5.0/5
- (6 jobs)
I am highly efficient and reliable professional who possesses a broad skill set for Mobile app and Web application development. (8 years of experience) A highly motivated, versatile expert, I have demonstrated expertise in software design and delivery covering mobile apps, and on-premise software. - Skills 1. Native app development ( 8 years ) : iOS ( Swift, UIKit, Swift UI ), Android ( Kotlin, Java, Jetpack Compose ) 2. Hybrid app development : Flutter ( 5 years ), React Native ( 3 years ) 3. Web development ( 5 years ) : PHP, Laravel, Angular, ReactKotlin
RESTful APIAmazon S3Amazon EC2App DevelopmentApple XcodeRxSwiftMySQLPHPReact NativeFlutterJavaAndroidSwiftiOS - $55 hourly
- 0.0/5
- (0 jobs)
I’m based in US Eastern Time and can help with software design, development, architecture, scaling, cloud migration, security, integrations, and end-to-end delivery. I specialize in fintech, blockchain, SaaS, and high-performance systems, solving challenges in scalability, performance optimization, event-driven processing, and regulatory compliance. Whether it's building from scratch or optimizing existing systems, I ensure secure, efficient, and scalable solutions. - **Fintech & Payments:** Designed and developed high-performance financial systems, banking wallets (300+ TPS), BNPL platforms, and stock trading solutions. Expertise in payment gateways, digital identity, and regulatory compliance (VAPT, OpenID Connect, Central Bank standards). - **Blockchain & Web3:** Built blockchain-based MVPs using CosmWasm, Neutron, and IPFS. Developed smart contracts, optimized decentralized identity, and integrated cross-chain interoperability. - **Microservices & Cloud:** Architected scalable, high-availability microservices using Kotlin, Java, Spring Boot, and Node.js. Expertise in Google Cloud, AWS, Azure, Kubernetes, and CI/CD pipelines. - **Data & Event-Driven Systems:** Implemented real-time data streaming with Kafka, TimescaleDB, and event-driven processing. Optimized databases (Postgres, MongoDB) for high-throughput applications. - **SaaS & PropTech:** Led backend development for SaaS platforms, handling scheduling, maintenance, and workflow automation. Integrated ML for predictive analytics and process optimization. - **Embedded Systems & High-Performance Computing:** Worked on GPU optimizations, FPGA-based simulations, CAN bus firmware, and test automation. Developed manufacturing automation and hardware testing software. - **Tech Leadership & Consulting:** Led multi-team agile development, mentored engineers, and provided architecture consulting. Specialized in cloud cost optimization, security best practices, and scaling enterprise applications. ### Experience Led the design and development of fintech solutions, including a banking wallet with over 300 TPS and 1M active users. Built a BNPL platform, integrating payment gateways, identity providers, and market data processing. Developed a stock trading platform using Kafka, TimescaleDB, and subscription-based payments. Managed five agile teams, ensuring seamless execution and compliance with regional financial regulations. Designed and implemented blockchain MVPs leveraging CosmWasm on Neutron, integrating on-chain data storage with off-chain solutions like IPFS. Optimized smart contracts for scalability, security, and real-world applicability. Worked on decentralized identity solutions and cross-chain interoperability. Architected and deployed fintech payment automation platforms, ensuring compliance with global banking standards. Built scalable NestJS microservices with event-driven communication via Kafka, deployed using Docker and Kubernetes. Developed GIRO transactions, corporate payment workflows, and high-volume transaction handling. Led backend development for SaaS features, designing microservices with Kotlin, Postgres, and Google Cloud. Migrated authentication from JWT to OAuth2, integrating an external identity provider. Optimized database performance, developed RESTful APIs, and ensured cloud-native deployment via Kubernetes and Pub/Sub messaging. Developed microservices for a PropTech platform handling maintenance jobs, scheduling, and invoicing. Integrated ML for job scheduling and QuickBooks for financial automation. Designed a high-availability system in Kotlin and Spring Boot, deployed on AWS. Optimized workflow automation, job assignments, and operational analytics. Architected a sustainability-focused SaaS platform, leveraging gRPC, RabbitMQ, Redis, and Elasticsearch. Led backend development for a railway asset management system, handling train scheduling, maintenance tracking, and asset lifecycle management using Java and Play Framework. Worked on GPU programming, system architecture optimization, and compute-intensive application performance tuning. Developed embedded firmware for CAN bus systems and real-time data processing. Designed and implemented test automation, and hardware verification tools. Provided technology leadership, architecture design, and cloud consulting for fintech and SaaS applications. Led cloud migration strategies, optimizing cost, security, and scalability for Azure, AWS, and Google Cloud deployments. Ensured compliance with best practices in fintech security, including VAPT audits and OpenID-based authentication layers. With expertise spanning fintech, blockchain, trading platforms, SaaS, and embedded systems, I deliver scalable, secure, and high-performance solutions, driving business growth and innovation.Kotlin
Vert.xMongoDBTradingViewFinTechPayment ProcessingPayment FunctionalityPayment GatewayAPI IntegrationSoftware ArchitectureJavaQuickBooks Online APINestJS DevelopmentApache KafkaBlockchain Architecture - $60 hourly
- 0.0/5
- (0 jobs)
SOFTWARE DEVELOPMENT ENGINEER Software Development Engineer with extensive experience in Agile Kanban and traditional software development methodologies. Skilled in taking software from requirements gathering through design, development, and deployment to a fully functioning production environment. Proficient in designing and developing backend web microservices using Kotlin, Java, and Spring for high-volume production systems. Experienced in front-end technologies such as iOS and web application development. Adept at creating comprehensive automated testing suites across various languages, including unit, component, and integration tests. Highly skilled at rapidly learning and applying new technologies.Kotlin
Web DevelopmentAPIGitLabCI/CDApache KafkaAutomated TestingAgile Software DevelopmentScrumJavaAngularFull-Stack DevelopmentSpring BootREST APIBack-End Development - $45 hourly
- 0.0/5
- (0 jobs)
I'm a Software Engineer with over 10 years of experience building scalable, high-performance systems across mobile and web. My core focus today is on backend-heavy, full-stack applications using Golang and TypeScript (Next.js). I started as an Android engineer, which taught me to think deeply about UX, performance, and software architecture. That experience sparked a curiosity that led me to explore backend and high-load systems, and eventually to dive into the full product development lifecycle. I thrive in fast-paced, startup-like environments where I can take ownership of complex problems and deliver clean, thoughtful solutions across the stack. I bring a product-oriented mindset, deep mobile experience, and a systems-level perspective to everything I build.Kotlin
Android App DevelopmentCloud ComputingRESTful APIPerformance OptimizationGraphQLCI/CDMicroserviceTypeScriptMongoDBPostgreSQLDockerReactNext.jsGolang - $75 hourly
- 0.0/5
- (0 jobs)
Looking for a top-tier mobile app that’s fast, intuitive, and built to scale? I specialize in designing and developing high-performance mobile applications for iOS and Android—crafted with clean code, beautiful UI/UX, and modern features users love. From MVPs to full-scale products, I bring deep expertise in cross-platform frameworks, native development, and seamless integration with backend services and APIs. Need AI features? I can supercharge your app with GPT-4, custom ML models, or real-time computer vision. ✅ Core Mobile Development Expertise: Cross-Platform Apps: React Native, Flutter Native Development: Swift (iOS), Kotlin (Android) State Management: Redux, Provider, Bloc UI/UX: Responsive design, Material Design, Apple HIG Backend Integration: Firebase, REST APIs, GraphQL, AWS, Node.js App Store & Play Store Deployment 🤖 AI & Smart Features (Add-On or Core): Chatbots & AI Assistants (GPT-4, OpenAI API) Computer Vision (TensorFlow Lite, image/video analysis) Voice-to-Text & Text-to-Speech (STT/TTS) Predictive Models & Recommendation Engines 🧠 Recent Work: 📲 A GPT-4-powered language learning app with voice conversation 📷 A mobile object detection app using TensorFlow Lite 🧘 A habit tracker & health app with AI-based user insights 🛒 A shopping app with product scanner & AI-based suggestions 💡 Why Choose Me? 6+ years of full-stack mobile app development Strong design-to-code mindset: pixel-perfect UI, buttery smooth UX AI-ready: I can integrate intelligent features without bloating your app Clean architecture, scalable code, and reliable performance Whether you're building a mobile-first startup or enhancing an existing app, I’ll help you launch a product that’s fast, intuitive, and future-ready.Kotlin
AI App DevelopmentAR PluginAR & VR ApplicationsReact NativeFlutterJavaObjective-CAndroid App DevelopmentiOS Development - $15 hourly
- 0.0/5
- (0 jobs)
With 11+ years of experience in mobile app development, I specialise in building modern, high-performance Android applications using Kotlin and Java. From sleek UI/UX to scalable architecture, I’ve led and contributed to projects across healthcare, eCommerce, and infotainment systems—delivering apps used by thousands. I’m well-versed in Android Studio, Jetpack libraries, and MVVM architecture, with hands-on expertise in API integrations (Retrofit, Firebase, RESTful services), Room/SQLite, and modern tools like Coroutines, LiveData, and Hilt. My cross-platform work spans Flutter and React Native, giving me a flexible edge in hybrid environments. I’ve also implemented CI/CD pipelines using Bitrise and managed deployments to the Play Store. Whether it’s performance optimisation, debugging with Logcat and Crashlytics, or collaborating via Git and Jira in Agile teams, I bring a complete Android development skillset to the table. If you're looking for someone who can hit the ground running, write clean modular code, and contribute beyond the screen. Let’s connect! :-)Kotlin
CI/CDREST APIJetPackGitAndroid UI DesignGoogle APIsAndroid SDKJavaFlutterFirebase Realtime DatabaseAndroidXamarinSQLiteFirebase Cloud Firestore - $20 hourly
- 4.7/5
- (1 job)
I'm a Dell Boomi Certified Professional Integration Architect. Implemented three full life cycle of end-to-end Integration projects with enhancements. Experience in implementation of Global ERP Integration projects: North America, LATEM, ANZ, APAC and EMEA. Profound Knowledge in Dell Boomi AtomSphere Platform, Integration Platform as a Service (iPaaS), Enterprise Application Integrations, Master Data Hub (MDH), API Management, Web Services and Software Development. Expertise in designing and developing complex integrations with ERPs such as Microsoft Dynamics 365 (D365), Oracle JD Edwards (JDE), Oracle NetSuite, SAP Business One; RDBMS, Salesforce, Workday, ADP, SAP Concur, Shopify, Magento, Coupa, OpenInvoice and many more using Dell Boomi AtomSphere platform.Kotlin
SwiftUISwiftDartFlutterTypeScriptReact NativeReactiOSAndroidFull-Stack DevelopmentWeb Application DevelopmentMobile App DevelopmentNode.jsJavaScript - $90 hourly
- 0.0/5
- (0 jobs)
I’m a seasoned Mobile App Developer with over a decade of experience, focusing on creating robust and high-performing applications. I graduated from university in 2013 and started my career with native app development for iOS and Android. In 2019, I switched gears to focus entirely on Flutter, using its capabilities to build cross-platform apps that boast seamless performance and beautiful UI/UX. My skill set includes leading cross-functional teams, thriving in agile development environments, and always staying updated with industry trends.Kotlin
iOS DevelopmentAndroid App DevelopmentSwiftMobile App DevelopmentDartFlutter - $80 hourly
- 3.3/5
- (42 jobs)
I am a mobile development expert with rich experiences and strong skills at building mobile app development. My expertise : - Social networking applications - Food delivery applications - Music player applications - Augmented reality (AR applications) - Dating applications - Fintech applications - E-commerce applications My core skill set: - Android ( Java / Kotlin) - iOS ( Swift / Objective C) - KMP (Kotlin Multiplatform) - Cross-platform app development ( Flutter) - RxJava , Dagger 2 , Koin, Kodein, Hilt , ButterKnife, Retrofit - Coroutines , Jetpack Compose - ArCore , OpenCv, ArKit - XML/JSON, REST/SOAP - Geolocation services , Firebase , In App Purchase , Android NDK - Social networks integration ( Facebook, Twitter, Instagram) - Github, Bitbucket, Gitlab - App architecture ( MVVM , MVP), Android Jetpack. I will keep your deadline and guarantee high quality.Kotlin
GitSketchCore JavaJetPackModel View ViewModelFirebaseGradleMobile App DevelopmentAndroid App DevelopmentRESTful ArchitectureAndroid StudioiOSiOS Development - $60 hourly
- 0.0/5
- (0 jobs)
I am reliable and passionate iOS/MacOS & Android developer with 8 years in software development. I pay great attention to details, delivering clean and maintainable code on time. My skills: ‣ iOS Mobile Apps development: Swift, Objective-C, iOS, Parse, UIKit/Cocoa Touch, Foundation, Alamofire/AFNetworking, In-App purchases/StroreKit, SpriteKit, CoreData, AFNetworking, CoreGraphics, MapKit, Accelerate, KeychainAccess, SwiftValidator, NSHash, AdSupport, AppsFlyer, GoogleConversionTracking ‣ Mac OS X development: Swift, Objective-C, Mac OS / XCode, Parse, Cocoa, Foundation, Alamofire/AFNetworking, XPCService, HelperTool implementation with admin privileges, IOKit, CoreWLAN, Security, SystemConfiguration, ServiceManagement, CoreFoundation, sys/socket, QuartzCore, KeychainAccess, CocoaPods ‣ Android: JSON / XML, Java, Animation, Creating and Consuming Web-Services / APIS, Google Maps API, Facebook API, Admob Ads Integration, In-App Purchase Integration, Databases(SQLITE, MySQL, SQL, CoreData), Push Notifications, FireBase, KIDS Educational apps ‣ Databases: MySQL, SQLite, MongoDB, CouchDB, PostgreSQL, Oracle ‣ Cloud server: Parse, AWS, iCloud, Dropbox ‣ Third party frameworks: Facebook, Twitter, LinkedIN, Instagram, Youtube ‣ Geolocation & google map/ GPS tracking, Google API, MapKit ‣ Online Payment: In-App Purchase, Apple Pay, Stripe, Braintree ‣ Chat & Messaging Engine: OpenFire, XMPP, Jabber, Socket.io ‣ Repository & Task management: Github, bitbucket, JIRA, Trello, PivotalTracker Good knowledge in code optimization, reducing code redundancies and write clear and loosely coupled code. Always work independently, polished leadership skills, with ability to motivate colleagues to increase productivity.Kotlin
FirebaseAWS AmplifyTypeScriptSQLiteNode.jsDartObjective-CJavaReact NativeSwiftFlutter - $65 hourly
- 0.0/5
- (0 jobs)
Honest, growth-oriented Software Engineer with an interest in creating tools that simplify people's lives. ▲ Core skill-set: ✔ Native: iOS with Swift, Objective-C ✔ Native: Android with Java, Kotlin ✔ Cross Platfrom: React Native, Xamarin, Ionic, Cordova, Flutter ✔ Web service: XML/JSON, REST/SOAP ✔ Device, Kit: Bluetooth Low Energy (BLE), iBeacon, Datzing, NFC ✔ Cloud backend: Parse SDK, Parse REST, Amazon S3 EC2 AWS, ✔ MySQL, SQLite, Oracle, SQL Server, ODBC , MongoDB, ✔ Facebook, Twitter, Linkedin, Instagram, Youtube, Pinterest ✔ Google Map, Geolocation, GPS ✔ iAd, Admob, Chartboost, Flurry, TestflightKotlin
React NativeObjective-CFlutterSwiftMobile App DevelopmentAndroid App DevelopmentiOS DevelopmentJavaLaravelNode.js - $70 hourly
- 0.0/5
- (0 jobs)
Hello! I am a Full Stack mobile app developer with over 10+ years of experience in software engineering and developing new features and mobile apps for different products and companies by using programming tools like Swift, Java, Kotlin, React, React Native, Node, Laravel etc. Will Always Be With You and Provide High Quality and Friendly Service. - Native & Hybrid Mobile Application Android, iOS, React Native, Flutter - Back-End Node.js, ExpressJS, Laravel, MySQL, MongoDB, RESTful, GraphQL (Apollo) - NFT Marketplace, NFT P2E Game Solidity, Truffle, hardhat, remix, Solana, Go, Rust, EVM Let me help you to grow your business successfully.Kotlin
JavaFlutterNode.jsLaravelReact NativeFirebaseObjective-CSwiftNative App DevelopmentiOS DevelopmentAndroid App DevelopmentMobile App Development - $40 hourly
- 0.0/5
- (0 jobs)
A passionate Android and Flutter developer with over 6 years of experience building mobile apps that are smart, scalable, and user-focused. Whether it’s optimizing warehouse workflows or creating secure internal apps for executives, I specialize in solving real-world problems through clean and maintainable code. My recent freelance work includes: IoT-based digital signage systems for factories (using Android TV + Arduino) Delivery management apps with offline capabilities, OTP login, PDF handling, and Firebase/Azure integration Internal communication platforms for CEOs with live video announcements, offline access, and calendar scheduling My toolbox includes Kotlin, Java, Dart, MVVM, Hilt, Jetpack, Firebase, SharePoint, and more. I love working on offline-first apps, integrating IoT data streams, and automating processes. What sets me apart? I bridge the gap between hardware, backend, and mobile systems I'm hands-on with every layer — from REST APIs to UI/UX I scale projects from idea to deployment — fast and reliably If you're looking for someone who gets the job done with solid code and clear communication, let's connect. I'm available for both short- and long-term projects. Let’s build something impactful together.Kotlin
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