Hire Vetted Mobile Application Engineers at Upstaff
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
Digital Platforms
Blockchain
Design and Creative
Quality Assurance
Project Management
Desktop Application
Writing and Translation
Scripting and Automation
Marketing and SEO
Embedded Systems
Low-Code and No-Code
GameDev
Industrial Engineering
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
Expert
Odesa, Ukraine
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
Senior
Ukraine
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.
Senior
Lviv, Ukraine
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.
Middle
Mykolaiv, Ukraine
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.
Senior
Georgia
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).
Middle
Poland
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;
Senior
Poland
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.
Senior
Warsaw, Poland
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.
Senior
Aldie, United States
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.
Middle
Nigeria
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.
Senior
Brazil
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.
Senior
Alexandria, Egypt
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.
Senior
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.
Senior
Bengaluru, India
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
Senior
Ukraine
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
Middle
Lviv, Ukraine
React Native
React
- Software Engineer with a Computer Science and Software Engineering background, bringing over 7 years of experience in developing mobile and web applications.
- Proficient in a spectrum of technologies, including React, React Native, TypeScript, JavaScript, and modern libraries and frameworks like Redux and Expo.
- Demonstrated leadership skills as a Team Lead, with a track record in managing development cycles, CI/CD pipelines, and team coordination to ensure timely delivery of high-caliber solutions.
- Adept in various domains such as IoT, utility infrastructure, and gambling.
- Strong emphasis on agile methodologies, clean code principles, and cutting-edge technology integration to build scalable and performance-centric applications.
Architect/Team-lead
Poland
Schedulers
Call Handling
Professional secretary and Virtual assistant with over 3 years of industry experience across various sectors including education, entertainment, health, and business. Demonstrated abilities in managing schedules, handling communications, and providing remote administrative support to enhance operational efficiency. Proficient in research, data entry, social media management, and a suite of other administrative tasks. Offering a 10% discount to the first new client, highlighting a commitment to providing valuable and affordable services.
Middle
Abuja, Nigeria
Facebook Auth
Dart
Kotlin
MVVM+Rx
GraphQL
Software engineer with 5+ years of experience specializing in Flutter development, adept at leading teams, and establishing development standards. Proven track record in architecting and deploying mobile apps with complex functionalities, including synchronous video players, multiple themes for whitelabel solutions, and comprehensive content management systems. Skilled in creating robust CI/CD pipelines (Codemagic, GitHub Actions) and implementing security measures aligned with backend infrastructures. Proficient in native plugin development across Kotlin, Java, Swift, and JavaScript. Educational background includes ongoing studies in Analysis and Systems Development, with strong problem-solving and team leadership abilities.
Senior
Brazil
Java 7yr.
Kotlin 5yr.
Facebook Auth 4yr.
Node.js 4yr.
Dart
Seasoned software engineer with 8 years of rich experience in mobile and full-stack development, particularly in Flutter, Kotlin, Node.JS, and Java. Proven track record in leading development teams and designing robust software architectures, evidenced by successfully delivering a critically acclaimed MVP for a hair color mixing app and dramatically improving an international social media app's performance by 80%. Proficient in Clean Architecture, DDD, CI/CD using GitHub Actions, and efficient RX programming. Strong background in software engineering with a Bachelor's in IT Administration and an Associate Degree in Software Engineering, coupled with hands-on experience in MVC, MVVM, SOLID principles, and various design patterns. Skilled in enhancing software scalability and performance, contributing to substantial revenue growth and client satisfaction through innovative solutions.
Senior
Yerevan, Armenia
Unreal Engine
Team Leadership
API
FDD
Software engineer with over 8 years of experience specializing in payment systems, e-commerce integrations, and both frontend and backend development. Proven track record in developing plugins for WooCommerce and Magento, creating Shopify payment applications, and constructing APIs for complex systems. Holds a B.Sc in Computer Science with a focus on Software Engineering. Proficient in PHP, Java, Go, Python, JavaScript, Bootstrap, and Tailwind CSS. Experienced in PostgreSQL, MySQL, CI/CD, and implementing monitoring and caching solutions.
Senior
Kenya
Flutter 4yr.
GCP 4yr.
Firebase 4yr.
Go
* Software engineer with over 4 years of experience in mobile app development, specializing in Flutter and proficient in Dart, Kotlin, and Go.
* Strong technical expertise in building robust backend systems, REST APIs, and has a keen interest in Blockchain technology within the GCP ecosystem.
* Demonstrated ability in web development using modern technologies including HTML, CSS, JavaScript, React, and NextJs.
* Active contributor to open-source projects, enhancing the value of platforms like APIDash and GoCoin.
* Holds a Bachelor's and a Master's degree in Computer Engineering, underpinning a solid understanding of software development practices.
* Recognized for building impactful mobile applications such as Edutive for education and Racha for addiction management.
Middle
Bamenda, Cameroon
Payment Gateways 5yr.
WordPress 5yr.
Laravel 7-9 3yr.
Unity 2yr.
Ant Design 1yr.
Developer
Expert
Caracas, Venezuela
Facebook Auth
Crashlytics
JavaScript
Slim
LCDP
An established Senior Flutter Fullstack Developer with over 20 years of experience in software engineering, boasting a strong technical background with a B.Sc. in Mathematical Physics. This engineer has specialized in cross-platform app design and development since 2011, first with the JavaScript framework Titanium and later adopting Flutter/Dart in 2020. Skilled in a variety of programming technologies, notably iOS, Android, and web development, with proficiency in frontend and backend technologies such as HTML/CSS, JavaScript, Firebase, node.js, and Python. Experienced in leading small development teams, this developer brings advanced knowledge in state management, API integration, and full-circuit backend system creation. The developer's commitment to quality and expertise in a diverse range of software methodologies and architectures is demonstrated by a history of successful projects in multiple business sectors, including fintech, healthcare, education, and animation.
Expert
Winchester, United Kingdom
Android APIs 4yr.
Swift 1yr.
ARCore
Jetpack Compose
Seasoned Android Developer and emerging iOS Developer with over 6 years of specialized experience in Android and over 1 year in iOS platform development. Expert in AR/3D reconstruction, excelling in Jetpack Compose, ARCore, and Open3D technologies, distinguished for advancing mobile systems and enhancing app performance. Proven track record in delivering cross-platform solutions, effectively managing app lifecycles, and leading development of AR-based applications. Recognized with an award for quality delivery and holds a Master's degree in Computer Applications, underpinning a strong technical foundation in mobile app development. Certified in Professional Scrum Master I, reflecting a deep understanding of Agile methodologies and software development best practices.
Senior
Montreal, Canada
FDD 6yr.
React
Vue.js
Ext JS
Senior Software Engineer with over 6 years in full-stack development and technical leadership. Specializes in the MERN stack, excelling in React.js, Node.js, and modern web technologies. Adept in architecting scalable solutions, microservices architecture, and utilizing DevOps practices such as Docker and Kubernetes. Instrumental role in projects like a customizable Hotel TV Application Platform and a GPS-enabled Golf Cart Navigation System. Proven experience in Agile/Scrum methodologies and mentoring developers. Notably led teams to enhance application performance and design secure, innovative systems for various industries.
Architect/Team-lead
Kotlin 6yr.
Java 5yr.
Android APIs 5yr.
Jetpack Compose 4yr.
Project Management 2yr.
Engineer with a B.Sc. in Mobile Development and over 4 years of hands-on experience in Android development, exhibiting a strong command of Kotlin, Jetpack Compose, and modern software engineering practices. Demonstrated expertise in app architecture modernization, reducing build times by 40%, enhancing app stability with comprehensive testing, and leading migration to scalable, modular architectures. Proven track record of impactful project management, having developed 600+ public-safety apps, and improved essential communication tools with a robust VoIP/messaging suite resulting in a substantial increase in user satisfaction. Competent in cross-functional team leadership, Agile methodologies, and continuous integration/delivery systems, making them a valuable asset for cutting-edge software development teams.
Senior
Birmingham, United States
JavaScript
TypeScript
React
React Native
Node.js
- Experienced Software Engineer with over 3 years at Securiti and prior engagement at Unique Software Development and KoderLabs, showcasing a strong engineering background and hands-on experience in contemporary software development practices and technologies.
- Proficient in JavaScript, TypeScript, React, React Native, Node.js, Nest.js; knowledgeable in MERN Stack, SQL, NoSQL, Azure, and skilled in managing software development life cycle (SDLC) in Agile environments.
- Demonstrated technical expertise through multiple project deployments on Android and iOS platforms, and adept in employing Test Driven Development with tools such as Jest for ensuring high-quality software.
- Bachelor of Science in Computer Software Engineering reinforcing a sound understanding of computer science fundamentals, paralleled by practical application in predictive analytics within the oil and gas industry.
- Valuable contribution to AI-powered cybersecurity solutions, enhancing privacy compliance through PRIVACI.ai platform development at Securiti, with focus on automation and scalability.
- Efficient in Agile software development, with capabilities in Clojurescript, parallel computing, and various programming methodologies, principles, paradigms, and patterns.
Senior
Karach, Pakistan
Illustration and icons 20yr.
Swift 5yr.
Objective-C
C++
- iOS software developer with 10+ years of experience. Participated in developing an architecting different iOS applications: from iOS AVFoundation players to iPad book readers, from hospitality and Digital Key experience to VPN and security (privacy) applications.
- Comprehensive knowledge of core iOS frameworks, excellent hands-on experience in CI/CD
pipelines setup, Unit testing and UI prototyping. I have complete knowledge of Apple development guidelines and put 20+ applications to the AppStore.
- Strong team player: Always set the product’s needs and team’s goal at the topmost priority. Occupied team leader positions and have lead my teams to growth, and have proven leadership experience.
- The scope of professional interests is in between cutting edge technologies: from modern REST API stack technologies to networking, from big-data and machine learning to computer vision applications.
- Work expectations would perfectly match with iOS application development and architecting; taking a part in prototyping of UI/UX with technical expertise; leading the team and perform technical expertise of any level. The main goal is to develop robust, advanced and feature-full applications for the world-wide auditory.
- Upper-Intermediate English
Expert
Kyiv, Ukraine
Android 7yr.
Flutter 3yr.
Java
Kotlin
- 16 years of experience in IT. 3 years of experience as a Flutter Developer.
- He has experience in developing applications from scratch using the Flutter framework.
- Intermediate English
- Available ASAP
Middle
Poland
LCDP 5yr.
Play Framework 5yr.
Swift 5yr.
Objective-C 5yr.
Kotlin
Senior Mobile Application Engineer with 17+ years of experience specializing in cross-platform mobile applications and SDKs. Expert in a wide range of frameworks and languages such as Capacitor, React, Next.js, React Native, Ionic, Flutter, Swift, Objective-C, Kotlin, Java, and proficient in CI/CD practices including Fastlane and GitHub Actions. Demonstrated ability in optimizing app performance, implementing push notification engines, and deploying production apps. Strong focus on secure, scalable API integration and backends, with a history of reducing project timelines through reusable components. Committed to agile methodologies and collaborative team environments, this engineer reflects a superior blend of technical prowess, industry insight, and hands-on experience across fintech, automotive, and healthcare sectors.
Expert
Swift 3yr.
Python 3yr.
XCode 3yr.
- Full-stack iOS Developer with over three years of experience, specialized in Swift, Python, and Xcode, with a successful track record of designing, developing, and launching high-quality iOS applications.
- Demonstrated expertise in the complete app development lifecycle, skilled in UI/UX design, front-end coding, back-end integration, and database management.
- Extensive 11-year background as a Data Analyst, proficient in data visualization, econometric modeling, and using tools like Stata, EViews, and Python to deliver data-driven solutions.
- Strong foundation in various statistical techniques and models, including ARDL, Spatial Autocorrelation, Probit and Multinomial Logit regressions, and VECMX model.
- Proven experience in project management, including conducting feasibility studies for PPP projects, and an adept understanding of risk assessment and stakeholder collaboration in the economic sector.
- A well-rounded educational background with a Master of Arts in Economics and a Bachelor of Arts in Economic Informatics, graduating with honors.
Expert