Hire Vetted Mobile Application Engineers at Upstaff - Page 1
All vetted software engineers you need to build AI, Web3, and data Products.
- Dedicated Full-time commitment for long-term or Time& Material for shorter or ongoing support
- Europe, Israel, LatAm, United States, Asia geography coverage
- Remote and hybrid engagement
- Trial period, no termination fees or hidden costs for transparent and risk-free onboarding.
Mobile Application
All
Web Application
Data and Analytics
Cloud and Operations
Mobile Application
Blockchain
Digital Platforms
Design and Creative
Quality Assurance
Project Management
Desktop Application
Marketing and SEO
Scripting and Automation
Embedded Systems
Writing and Translation
Low-Code and No-Code
GameDev
Industrial Engineering
Xamarin 9yr.
.NET 9yr.
SQLite 9yr.
.NET MAUI 4yr.
AWS
- Engineer with 9+ years in mobile app development using Xamarin, Xamarin.Forms, and .NET MAUI, delivering cross-platform solutions for US, UK, and UA clients.
- Expertise in MVVM frameworks (MvvmCross, MvvmLight) and database technologies including SQLite and Realm.
- Proven track record leading teams and architecting scalable apps with CI/CD pipelines using Jenkins, AppCenter, and Azure DevOps.
- Azure, AWS, and GCP cloud services
- Experience integrating complex payment systems (Stripe, ACH, PayPal) and backend services with REST APIs and EFCore.
Node.js
React
TypeScript
AWS
- Senior JavaScript Engineer with 8+ years of experience; MS in Computer Science and Software Engineering.
- Node.js, TypeScript, PostgreSQL, and AWS; High-load projects with JS/TypeScript, Java, QT, and C++.
- AWS serverless, Lambda functions (migration architectures, reduced infrastructure costs by 40%, microservices that handle 10K+ concurrent requests with latency less than 200ms); Experience migrating monolithic systems to serverless and microservice architectures, optimizing performance and reducing infrastructure costs (~40%);
- Skilled in SDLC practices, including Agile/Scrum, CI/CD pipelines with GitHub Actions and Docker, and pre-test development using Jest and Playwright;
Objective-C 10yr.
iOS 10yr.
C++ 10yr.
Swift 5yr.
- Served as a Senior Software Developer in the Two German Automotive Navigation Projects, focusing on System Team operations as well as Map and Routing domains.
- VPN and Network Filtering Development: Extensive experience developing VPN solutions, including cross-platform engines for KeepSolid’s VPN Lite, and expertise in low-level network filtering, proxies, and handling internet traffic.
- iOS Development Expertise: Over 10 years of hands-on experience with iOS development, including business apps and secure communication tools, with proficiency in Swift and Objective-C.
- C++ Proficiency: Strong background in C++ for developing core network functionalities, optimizing performance, and building cross-platform applications.
- Enterprise Application Development: Skilled in developing enterprise-level applications, including parental-style internet filters and device policy management tools.
- Agile Methodologies: Proven track record of working in Agile Scrum environments, delivering high-quality software with fast iteration and strong collaboration.
- Leadership and Team Collaboration: Experience as a Tech Lead, mentoring teams, and coordinating with stakeholders to resolve issues and implement new features.
- Available to start ASAP
React 6yr.
React Native 2yr.
- 9 years of proven professional expertise in the IT industry;
- Advanced experience in Web Development using JavaScript 7+ years;
- Solid experience in software development using ReactJS and React Native (6+ years); 3 Years with Node.js
- Good experience in Web development using PHP;
- Beginner experience in Web Development using Ruby on Rails;
- Beginner experience in Web Development using Java;
- Upper-Intermediate English
Kotlin 5yr.
Java 5yr.
Ivan is a Lead Kotlin/Java Engineer with solid experience in backend and Android development. He builds reliable and maintainable applications, works well with cross-functional teams, and enjoys improving codebases and system architecture. Ivan is comfortable mentoring others and contributing to both mobile and backend projects, making sure they run smoothly and efficiently.- Software Engineer with 5+ years of experience in developing Android and backend solutions in the healthcare, fitness, and automotive industries;
- Strong Skills with Kotlin, Java, and TypeScript, creating Android applications on Jetpack Compose, Firebase, Android SDK, KMM, as well as backend solutions on Spring Boot (and basic experience with Node.js / React for integrations and prototypes);
- Experienced with AWS (Serverless, Lambda, S3, API Gateway) and GCP, builds cloud infrastructure, and is undergoing Google Cloud certification;
- Skilled with Firebase as a backend platform;
- Experience CI/CD, Docker, GitHub Actions, works according to Agile principles;
- Interested in implementing AI models in production solutions.
Java 5yr.
Spring 3yr.
React 2yr.
EDUCATION & CERTIFICATIONS
- Matric certificate (high school)
- TEFL Level 5 Certified
- First aid certification
- CPR certification
C# 10yr.
Xamarin 7yr.
React Native 4yr.
React 4yr.
.NET MAUI 3yr.
- Lead Software Engineer with 10+ years in cross-platform enterprise app development using .NET MAUI, Xamarin, and Blazor.
- Expertise in C# (.NET 6/7/8), XAML, React Native, Azure, Firebase, and microservices architecture.
- Proven impact: 35% latency reduction in mobile workforce apps and 40% stability improvement via Firebase Crashlytics integration.
- Skilled in CI/CD pipelines, automated testing (Katalon), and cloud deployments on AWS and Azure.
- Strong background in offline-first mobile solutions, AI agent workflows, and multi-platform app lifecycle management.
RESTful API
Backend
React
I'm a Senior Software Developer with 13+ years of experience building scalable web applications for international remote teams. My primary stack includes React, Node.js, Python, PostgreSQL, and cloud platforms such as Google Cloud and AWS. Recently, I've been developing AI-powered web applications and automation workflows while collaborating with distributed teams across the US, Singapore, and Europe. I enjoy creating clean, maintainable solutions, continuously learning new technologies, and contributing to products that deliver real business value.
Kotlin
Java
Facebook Auth
Microsoft Power Platform
Node.js
- Technical Team Lead with experience in designing and delivering scalable mobile applications using Kotlin, Java, Flutter, React Native, and Kotlin Multiplatform (KMP).
- Proficient in Android development with expertise in MVVM, MVI, Clean Architecture, and backend API development using Node.js and Ktor.
- Skilled in integrating complex features such as payments, location services, and real-time communication (WebSockets, WebRTC, Agora) across diverse domains
- Experienced in mentoring teams, managing client expectations, and delivering production-ready applications with high code quality and performance optimization.
React Native 2yr.
JavaScript 2yr.
TypeScript 2yr.
Node.js 2yr.
Express JS API (NodeJS) 2yr.
Main Achievements:
- Built scalable full-stack web applications using modern frameworks and DevOps practices for seamless deployment.
- Developed cross-platform mobile apps with React Native, delivering high-performance user experiences.
- Automated CI/CD pipelines to improve deployment efficiency and reduce manual errors.
- Created responsive front-end solutions that enhance user engagement and site performance.
- Earned certifications in React and DevOps to stay updated with industry best practices.
React 3yr.
React Native 3yr.
JavaScript
TypeScript
- Software engineer with 4+ years in cross-platform mobile and front-end development, specializing in React, React Native, and Flutter.
- Proficient in state management (Redux Toolkit, BLoC, Redux Saga), API integration, CI/CD pipelines, and performance optimization.
- Experienced in Agile methodologies, leading teams, mentoring developers, and delivering scalable applications for Android and iOS.
- Developed complex apps featuring real-time communication (Socket.IO), multi-authentication, payment integration (Stripe), and cloud services (Firebase, AWS Amplify).
- Strong background in computer science engineering , applying clean architecture and modular design patterns in production projects.
JavaScript 10yr.
React Native 5yr.
React 5yr.
TypeScript 3yr.
Senior Front-End Developer (React Native mobile / React web) with 10+ years of experience. Skilled at JavaScript, TypeScript, and React. I’ve worked on various projects and have extensive expertise. I have experience developing projects from scratch through to market release.
TypeScript 1yr.
React 1yr.
Hono 1yr.
React Native
Prisma
- Proficient in full-stack development with expertise in TypeScript, React, Rust, Swift, and backend technologies including Prisma, PostgreSQL, and Bun, demonstrated through building scalable CMS, native macOS apps, and terminal tools.
- Skilled in asynchronous programming, Rust backend refactoring, and cross-platform development using Tauri and React Native, enhancing startup latency and memory usage.
- Hands-on with CI/CD pipelines, AWS deployment, and monitoring to maintain 99.9% uptime, alongside advanced automation integrating AppleScript and AI-driven transaction parsing.
React
TypeScript
Python
FastAPI
- 10+ years of experience delivering scalable SaaS platforms and cloud-native systems using React, TypeScript, Python (FastAPI, Django), Node.js, and AWS.
- Proven expertise in legacy system modernization, reducing API response times from 3s to under 1.8s by migrating C#/.NET services to modern microservices.
- Strong in system design, distributed systems, event-driven architectures with Kafka, Celery, Redis, and performance optimization.
- Skilled in full SDLC ownership, CI/CD pipelines, containerization (Docker, Kubernetes), and infrastructure as code for reliable cloud deployments.
React Native
TypeScript
React
- Senior React Native engineer with 9+ years in mobile and web development, including 6+ years with React Native in production.
- Delivered cross-platform applications across healthcare, fintech, real estate, and logistics domains, including patient-facing clinical trial apps (HIPAA-compliant).
- Experience includes real-time features using WebRTC, offline-first data handling, and performance optimisation for mobile apps.
- Worked with React, Next.js, GraphQL, and AWS; contributed to mobile architecture and led frontend teams.
React Native
React
- Senior React Native engineer with 7+ years building mobile apps with React Native (Expo, CLI) and React, focusing on scalable app architecture and feature delivery.
- Experience with video features in social and communication apps (live streams, video calls, feed-based consumption), including HLS playback, buffering, and performance tuning on mobile.
- Worked on mobile-first video UX: smooth playback, fast loading, adaptive bitrate, and seamless navigation between video items.
- Hands-on with monetization, analytics, and integrations (Firebase, GraphQL), plus mentoring and collaboration across product and backend teams.
React Native
React
TypeScript
- 6+ years with Front-end/Mobile: cross-platform applications, React Native, React.
- IoT & hardware: BLE and Wi-Fi device pairing (Soft-AP, Protobuf), custom native bridges (iOS/Android) for hardware communication - Ninja Pro Connect app with 100K+ downloads
- Short-form video: TikTok-style educational app with HLS playback (Expo Video), player pooling, lazy loading of video batches, and quality fallback for low-end devices
- Production tooling: push notifications (Firebase + Notifee, Android foreground/keep-alive services), analytics/session replay (Mixpanel, LogRocket, Sentry, Bugsnag), CI pipelines, ESLint + pre-commit quality gates.
- Familiar with New Architecture (Fabric, TurboModules, JSI, Hermes)
JavaScript 16yr.
React Native 10yr.
TypeScript
- Senior React Native Developer with 16 years in software development, specializing in cross-platform mobile applications for iOS and Android using React Native and Expo.
- Proficient in JavaScript, TypeScript, Node.js, and backend technologies including Express.js, MongoDB, and MySQL, with extensive experience in API design and integration.
- Expertise in AI-assisted development tools (Claude Code, Cursor, GitHub Copilot) to accelerate delivery and improve code quality.
- Skilled in modern CI/CD pipelines (GitLab, GitHub Actions, Fastlane, Azure DevOps) and testing frameworks (Jest, Detox) ensuring robust, maintainable software.
JavaScript 10yr.
React 8yr.
Node.js 8yr.
TypeScript 5yr.
- Software engineer with 10+ years in full-stack JavaScript, specializing in scalable web, hybrid mobile, and cross-platform desktop applications using React, Next.js, Node.js, and TypeScript.
- Proven track record in designing microservices, REST/gRPC APIs, and cloud infrastructure automation with AWS, Docker, Kubernetes, and Terraform.
- Led development of enterprise-grade platforms including e-commerce, telecom microservices, and aviation weather systems, emphasizing modularity, security, and performance.
- B.Tech in Computer Science with strong open-source contributions to Ionic and Capacitor ecosystems, demonstrating commitment to community and innovation.
.NET 7yr.
FDD 3yr.
Solidity
Linea
- Proficient in full-stack development with expertise in Flutter, .NET, Solidity, and blockchain technologies, delivering robust and scalable solutions.
- Demonstrated leadership in managing projects and teams, including roles as Project Development Manager and Senior Developer.
- Experienced in SDLC best practices, software architecture, and cross-platform development, with a strong focus on Web3 and blockchain integration.
- Proven track record in freelance and corporate environments, contributing to diverse projects across Brazil and Canada.
Python 4yr.
TypeScript 4yr.
React 4yr.
React Native 4yr.
FastAPI 3yr.
- Over 4 years of full stack development experience specializing in React, React Native, TypeScript, and Python (FastAPI) with strong expertise in system architecture, database management (PostgreSQL, MongoDB, Firebase), and Docker deployment.
React 5yr.
React Native 3yr.
- Senior Frontend Engineer with 5+ years of experience specializing in React JS, React Native, and Expo.
- Expert in architecting scalable monorepos using Rspack and Module Federation, and implementing cross-platform solutions with Tamagui design system to accelerate feature delivery.
- Proficient in integrating complex payment systems (crypto and traditional), KYC/AML flows, real-time multilingual chat via WebSockets, and push notifications with Novu.
Swift 2yr.
IOS SDK 2yr.
UIKit 2yr.
SwiftUI 2yr.
Objective-C
- iOS Developer with 2+ years of experience delivering high-performance VPN and utility apps, proficient in Swift, Objective-C, and modern concurrency (async/await).
- Skilled in multiple architectures and design patterns including MVVM, MVC, VIPER, TCA, and Coordinator.
- Expertise in full mobile development lifecycle from UI implementation based on Figma designs to App Store deployment, with strong integration experience (Adapty, Amplitude, AppsFlyer, Firebase).
TypeScript
Node.js
React
- Senior Full Stack Engineer with 5+ years of experience developing web and mobile applications;
- Implemented APIs and microservices with Node.js, Nest.js, PostgreSQL, including caching, queue management, and AWS infrastructure (Proxet, NovaPay, and Web3 Startup);
- Built interfaces and component libraries using React, Vue, React Native, Next.js, TypeScript, and JavaScript (Proxet (SSR web platform), NovaPay (mobile app), and Web3 Dashboard);
- Experienced in fintech, Web3, and enterprise platforms, delivering production features, maintaining existing systems, and working in Agile teams.
UI/UX
Palm Infotech is a leading Software and App Development Company offering tailor-made mobile and web solutions for startups, SMEs, and enterprises. We specialize in Android, iOS, NodeJS, React Js, Fluter and cross-platform apps with ERP integration, and are known for building high-performance products like fantasy sports apps, astrology-based platforms, food and grocery delivery apps, taxi booking systems, clinic management tools, and other on-demand applications. From MVP implementation to robust order management systems, our team focuses on scalable, intuitive, and AI-powered apps that align with business goals. With expertise in UI/UX, backend architecture, and third-party integration, we deliver end-to-end development along with ongoing maintenance and post-launch support. Palm Infotech is trusted for its timely delivery, responsive communication, and quality-driven development across industries.
React 2yr.
Facebook Auth 1yr.
Java 1yr.
- Front-End Developer with expertise in React.js and Flutter, delivering responsive, high-performance web and cross-platform mobile applications.
- Proficient in translating UI/UX designs into scalable, pixel-perfect interfaces, with strong skills in component-based architecture and performance optimization.
- Experience in Agile methodologies, collaborating with cross-functional teams to deploy digital solutions and enhance user engagement.
- Background in Agricultural & Bio-environmental Engineering with additional certifications in Business Strategy, CRM, HR, and Project Management.
- Hands-on knowledge of blockchain technology and decentralized platforms, complemented by full-stack development experience using Java and Asp.Net.
Dart 5yr.
Kotlin 3yr.
GraphQL 3yr.
MVVM+Rx 3yr.
Software engineer with 5+ years of experience, specialized in Flutter development and project architecture. Core competencies include mentoring Flutter teams, setting development standards, and implementing CI/CD pipelines. Impressive track record of creating applications using MVVM, GraphQL, RestAPI, and a range of other technologies like Firebase and Chromecast, with experience in developing native plugins with Kotlin, Java, Swift, and JavaScript. Demonstrable expertise in enhancing the performance of legacy projects and modularizing project structures. Education includes ongoing studies in Analysis and Systems Development and a background in Computer Technology. Highly skilled in front-end development, database design, DevOps practices, and mastering various programming languages. Proficient in applying Agile principles and proven problem-solving abilities, coupled with strong leadership and mentoring skills.
React
React Native
HTML/CSS Preprocessors
JavaScript
Next.js
Highly skilled ReactJS and React Native developer with 5+ years of experience in crafting robust web and mobile applications. Strong background in mechanical engineering with a transition to software development, showcasing adaptability and a multifaceted skill set. Adept at leading projects, such as a significant migration to new web apps with React and real-time APIs using RabbitMQ, and creating survey tools with AI-powered analytics. Possesses hands-on expertise in React, Redux, Flutter, NextJS, NuxtJS, and modern frontend technologies, complemented by a track record of successful cross-functional collaboration. Contributed to multiple large-scale projects, notably enhancing customer experience through AI-powered social media insights. Successfully completed a frontend-focused education at ITI, underpinned by a BSc in Mechanical Engineering and professional certifications including PMP and JavaScript algorithm mastery.
ASP.NET Core Framework 8yr.
C/C++/C# 8yr.
React Native 2yr.
Software engineer with 8 years of experience, including specialization in React native, .Net development, and a strong background in the banking sector, HR, health, and biometric device integration. Proven track record in designing resilient cloud solutions with Microsoft Azure, and expertise in full SDLC, TDD, MVC, CQRS, and microservices architecture. Has developed scalable applications using C#, ASP.NET Core, React/React native, and Entity Framework, backed by a solid foundation in computer science with an MSc in Data Science and Business Analytics. Recognized for implementing efficient integrations with Central Bank systems and third-party APIs, enhancing financial technology ecosystems.
Objective-C 8yr.
API 8yr.
Swift 5yr.
IOS SDK 5yr.
Seasoned iOS Developer with 8.6+ years of experience in the IT industry, specializing in mobile application development using Swift and Objective-C. Well-versed in Cocoa Touch, iOS SDKs, and frameworks like AFNetworking, with hands-on experience using Pods and Git for dependency and version control.Strong academic foundation with a B.Tech from Kuppam Engineering College (JNTU), and a proven track record of delivering high-quality applications using MVC and MVVM architectures in Agile environments. Expertise includes BLE integration, QRCode/Barcode scanning, biometric authentication, memory management, and performance optimization.Successfully contributed to multiple enterprise-level apps, including Rinnai Central, Honda PSP, and VELYS Patient Path, improving user experience, reliability, and code efficiency across contract and full-time roles.
JavaScript 4yr.
React Native 4yr.
- A detail-oriented software engineer with 4 years of experience in web and mobile development.
- Intermediate English
- Available in two weeks
JavaScript 3yr.
React 1yr.
- 3 years of experience in the software development. Working on mobile and web development using JavaScript frameworks like React, React-native, Redux. Highly experienced in creating custom components according to the design. Confident with my skills in Unit Testing, HTML, CSS, API integration.
- Intermediate English
- Available ASAP