Hire Vetted Mobile Application Engineers at Upstaff - Page 2
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
Java 6yr.
Android 5yr.
Kotlin 3yr.
- Over 5 years of expertise as an Android developer specializing in Kotlin. Experienced in leading and collaborating with development teams to ensure successful project delivery.
- Skilled in introducing new functionalities, transitioning projects from Java to Kotlin, and adhering to WCAG accessibility standards.
- Proficient in software architecture, quality assurance, and agile methodologies. Also experienced in Java software engineering, web development, and instructional roles.
- Comprehensive understanding of Android UI/UX principles, clean architecture, and a range of libraries and tools.
- Solid proficiency in Java, Kotlin, RxJava, Coroutines, Android Jetpack, Firebase, REST APIs, and various development and debugging tools.
- English proficiency at an upper-intermediate level.
Available to start immediately.
Senior
Poland
Delphi 25yr.
SQL
Visual Basic
Pascal
Software engineer with over 25 years of development experience, possessing extensive expertise in Delphi (VCL/FMX) and database management across various sectors. Notable for implementing performance-focused custom applications, this engineer's technical proficiency also spans C#, Visual Basic, SQL, and multiple database systems. They have a strong track record in system administration and IT support, having worked with reporting tools like Crystal Reports. Holds a Diploma in Computer Program from BIG SERVICE, showcasing a solid foundation in computer science.
Expert
Antananarivo, Madagascar
$40/hr
$5000/month
$5000/month
iOS 11yr.
Swift 5yr.
Objective-C 5yr.
Java 3yr.
Spring Boot 3yr.
Expert with iOS swift/ Objective C development
Nearly 2 years experience on Java Spring Boot development
Senior
Karachi, Pakistan
React
React Native
JavaScript
TypeScript
- 7+ years of expertise in frontend and mobile development with a strong command of ReactJS, React Native, and TypeScript, delivering scalable cross-platform applications.
- Proven leadership in architecting solutions, leading React/React Native teams, and driving technical decisions aligned with product and design goals.
- Hands-on experience with modern web and mobile technologies, including Next.js, Redux, REST API, GraphQL, and native Android/iOS modules.
- Skilled in CI/CD pipelines, code quality tools (Eslint, Prettier, SonarQube), and testing frameworks (Jest, Detox, Playwright), ensuring robust software delivery.
- Master’s degree in engineering from a technical university, with a solid foundation in software development lifecycle, Agile methodologies, and responsive, accessible UI design.
Senior
Ukraine
React Native 5yr.
JavaScript 5yr.
TypeScript
- 5+ years of expertise in React Native development, specializing in cross-platform UI architecture, Redux state management, and native module integration.
- Proven leadership in managing complex projects, including award-winning apps, with strong skills in asynchronous workflows using Redux Saga and real-time data sync via Firestore.
- Skilled in integrating payment systems (Stripe, PayPal, RazorPay), location services, push notifications, and offline data persistence using SQLite, Realm, and AsyncStorage.
- Experienced in building user-centric solutions for diverse domains such as crisis communication, legal reference, and sports coaching, leveraging Context API, full-text search, and analytics dashboards.
- Holds a Bachelor in Computer Engineering, proficient in JavaScript, TypeScript, and modern development tools (VS Code, Android Studio, XCode) across MacOS, Windows, and Linux environments.
Senior
India
.NET Core 8yr.
TypeScript 6yr.
React 6yr.
React Native 6yr.
Node.js 6yr.
- Full-stack engineer with 6+ years of expertise in TypeScript, React, React Native, Node.js, and .NET Core, delivering scalable B2B and healthcare applications with 40% latency reduction through query optimization.
- Proficient in integrating analytics SDKs (Mixpanel, Firebase, AdMob) and implementing secure JWT authentication and role-based access control in cross-platform mobile apps.
- Experienced in CI/CD pipelines using GitLab CI/CD, automated testing (Jest, Cypress), and cloud deployments on AWS and Docker, enabling rapid iterative releases and A/B testing.
- Strong background in SQL databases (PostgreSQL, MySQL, SQL Server) with advanced query optimization for analytics-driven growth metrics.
- Holds an MSc in Computer Science and IT, skilled in modular architecture, feature flags, and AI-augmented development to accelerate coding and improve UX flows.
Senior
Germany
JavaScript 5yr.
Node.js 5yr.
React 5yr.
Vladyslav S. is a Senior JavaScript Developer with 6+ years of experience specializing in React.js, React Native, and Node.js. Experienced with AWS services (Lambda, ECS, RDS, DynamoDB), Firebase, Terraform, and CI/CD pipelines (GitHub Actions, Docker). Proficient in REST APIs, state management (Redux, MobX), and modern frontend frameworks like Next.js and Angular. Strong team collaborator with clean code practices and a focus on scalable architecture.
Senior
Ukraine
Swift 6yr.
UIKit 6yr.
RxSwift
Combine framework
Crashlytics
Senior iOS Developer with over six years of experience in developing high-performance mobile applications. Expertise in designing scalable architectures such as VIPER, MVVM, and Redux and in optimizing app performance through in-depth profiling and code refactoring. Proven track record of improving messaging app stability by 20%, reducing memory usage by 30%, and enhancing fin-tech app user interfaces with custom UI components and animations. Delivered an innovative Bluetooth mobile app, enhancing building time by 25% and memory usage by 15%. Proficient in Swift, UIKit, RxSwift, Combine, Firebase, and Mapbox, with the ability to collaborate seamlessly with cross-functional teams. Possesses an advanced level in English and a strong grasp of various development frameworks and tools.
Senior
Facebook Auth 3yr.
Dart 3yr.
A seasoned software engineer with 3 years in mobile development, specializing in Flutter and possessing a strong foundation in Java full stack technologies. Spearheaded development of sophisticated mobile applications including fintech and social media platforms, notably integrating third-party services like Plaid and implementing real-time tracking systems. In addition to solid UI/UX design skills, boasts proficiency with Spring MVC, Hibernate, and MySQL, complemented by full-stack Java development training. Holds a Bachelor's degree in Computer Science and has contributed to open-source projects, showcasing practical expertise in a variety of technical environments. A proven track record of architecting robust applications and optimizing performance through advanced programming techniques and methodologies.
Senior
Sirhind, India
React Native
Next.js
React
Redux-Saga
With over 12 years in the software industry, this Senior Full Stack Technical Lead excels in leading teams and architecting a wide range of applications using technologies like ReactJS, NextJS, React Native, Flutter, and NodeJS. This includes proficiency in Redux-Saga and Redux-toolkit for state management, as well as utilizing MaterialUI for UI development. Versed in both front-end and back-end coding languages, methodologies, and databases, they consistently deliver complex projects, such as a BBL Bank web application and managing a city center web portal in Saudi Arabia. Their engineering prowess is backed by a Diploma in Software Engineering and a B.Sc., reinforcing their strong theoretical foundation. Methodically familiar with SDLC and agile practices, they are adept at project management using JIRA and have experience in AWS environments. Additionally, their technical toolkit encompasses CI/CD pipelines with Jenkins and CircleCI, and version control expertise with Github and Gitlab.
Architect/Team-lead
Ahmedabad, India
Facebook Auth 5yr.
Dart 5yr.
Power BI 5yr.
Apache Hive 5yr.
Crashlytics 5yr.
Senior Software engineer with over 5 years of experience specializing in Flutter development for cross-platform mobile apps. Mastery in architecture patterns like MVVM, MVP, BLoC, and Clean Architecture, combined with advanced skills in Dart, Flutter, Firebase, and WebRTC. Demonstrated capability in building complex real-time communication applications and ensuring data security aligns with OWASP guidelines. Adept in state management using BLoC, Provider, and Riverpod, and proficient in development tools like Visual Studio Code, Android Studio, Git, and Flutter Inspector. Significant experience with database technologies like Hive, SQFlite, and Firestore, and contributions to enterprise-level projects ensuring performance optimization and crash-free user experiences.
Senior
PHP
JavaScript
jQuery
MySQL
PostgreSQL
Expert software engineer with 20+ years of experience specializing in backend and full-stack development. Proficient in an array of languages like PHP, Visual Basic, and JavaScript, with a strong foundation in database architecture across MySQL, PostgreSQL, and SQL Server. Demonstrates a consistent track record of optimizing system performance and scalability, evidenced by a 40% reduction in load times and a successful migration from Delphi to PHP. Holds an engineering degree and numerous technical certifications, underpinning a solid educational foundation in computer science. Recognized for advanced technical skills and delivering high-impact projects such as ScanChex Mobile and comprehensive payroll and administrative systems.
Expert
Maracaibo, Venezuela
Quadient Inspire 5yr.
React Native 3yr.
React 3yr.
relational databases
- Full Stack Developer with 5+ years of experience building and scaling web & mobile applications using the MERN stack, React Native, and DevOps practices, including Docker, CI/CD, and AWS.
- Adept at designing, developing, and deploying production-ready MVPs for various clients, with a record of 25+ successful product launches.
- Proficient in React.js, such as employing advanced state management with Redux and React Context, and optimizing performance with best practices like lazy loading and code splitting.
- Technical writer and educator with content reaching over 700K readers, contributing to freeCodeCamp and other tech platforms, enhancing knowledge sharing within the developer community.
- Holds a BTech in Computer Science, providing a solid foundation in software engineering principles; experienced in collaborating with design teams to create fluid, responsive UI/UX for web applications.
- Demonstrates a deep understanding of software development life cycle and modern development methodologies, as well as a knack for teaching coding and assisting clients with SEO and organic growth.
Middle
Android
* Software engineer with 6+ years in mobile Android (Kotlin, MVVM and Clean Architecture).
* Master's degree in Computer Engineering
* Experience with Android SDK, Jetpack components (Room, Dagger/Koin Compose), Android Views, and integrating with RESTful APIs and various hardware (e.g., portable printers, scanners, Bluetooth devices). and REST API integration, Git/GitFlow, and API integrations.
* 4 years with ERP systems (internal use: employees, warehouse, workers "in fields") for mobile devices and hardware (e.g., portable printers, scanners, Bluetooth devices).
* Led a team of Android developers, mentoring junior engineers, conducting code reviews, and coordinating with cross-functional teams to ensure the timely delivery of high-quality products.
* Passionate about delivering user-friendly solutions that solve real-world problems.
Middle
Cherkasy, Ukraine
Scrum
MongoDB
React
At DBB Software, we deliver custom software products tailored to your needs, leveraging our set of pre-built solutions that reduce your development time by up to 50%.
As a certified AWS Partner, we excel in migrating any system or workload to the cloud, ensuring your setup is up to industry standards and primed for success.Our services:
Web Development
Mobile Development
DevOps Engineering
AI/ML Development
Software Integration (CMS/CRM/ERP)
AWS integration
Dedicated Team
Team Extension
IT Support & OperationsIndustries:
E-commerce
Real Estate
Social Network
HR platforms
Logistics
HealthCareOur Approach:
We use pre-built solutions with ready-made blocks to speed up development, leading to:
50% reduction in development time.
Up to 30% faster POC and prototype stages.
50% less planning time.Why DBBS?
10+ years of industry experience
100+ skilled software engineers
5+ years is the average employee tenure.
6+ years of client lifetime
We’ve successfully completed over 100 projects for industry leaders such as JLL, WeWork, RedAlpine, Philips, DispatchHealth, and Doctify, helping secure substantial funding for our clients, including $50M for a healthcare startup, $11M for a marketplace, and $5M for a real estate platform.
Expert
Poland
Android 12yr.
Flutter 6yr.
iOS
- Over 12 years in the tech industry, my mission is to innovate with cutting-edge technologies, fostering a team-driven environment where diverse perspectives thrive
- 6 years of experience with Flutter;
- Committed to developing robust products that seamlessly integrate mobile and cloud technologies, aligning with our organization's culture of continuous learning and improvement.
- My expertise in mobile development and enterprise systems, underpinned by a solid understanding of business ownership, empowers us to create solutions that resonate with our users' needs.
-Over the past 6 months, my role team-lead and Head of R&D has centered on assembling and leading a dynamic team adept in technologies such as Flutter, Golang, Java, Angular, and React.
- Dedicated to leveraging cloud services like AWS and Google Cloud Platform, ensuring our products are scalable and reliable.
Architect/Team-lead
Novi Sad, Serbia
Java SE
Kotlin
Android
Android developer with a strong foundation in software engineering, holding a Bachelor's Degree in IT and Software Engineering, and boasting over 4 years of professional experience. Expertise in Java SE, Kotlin, and Android SDK underscored by proficiency in MVVM, MVP, and Clean Architecture, ensuring scalable and maintainable code. Adept in modern Android development tools like Jetpack Compose and Navigation Component, coupled with mastery in Networking & APIs like Retrofit 2 and Stripe API. Demonstrated abilities in asynchronous programming using Kotlinx Coroutines, and commitment to quality through rigorous test case development. Proven track record in contributing to all phases of the SDLC in various projects, from user interface implementation to application deployment for mobile and Android TV platforms.
Middle
Ukraine
Android APIs 5yr.
LCDP
Microsoft Power Platform
Software engineer with hands-on experience in Android development, boasting a solid engineering foundation with a Bachelor's degree in Business Informatics. Demonstrates proficiency in multiple architectures, including MVVM and MVP, and technical fluency in Kotlin, Java, and Android Studio. Known for contributing to complex projects using tools like Dagger2, RxJava, and Realm, and adept at optimizing app performance and integrating third-party libraries. Played a key role in the development of applications in sectors such as e-commerce, delivery, and CRM, leveraging sound knowledge in material design guidelines and handling API interactions. Emphasizes a thorough understanding of project management and SDLC, with a strong ability to lead and collaborate within cross-functional teams.
Middle
Tirana, Albania
NativeJS 15yr.
Play Framework 5yr.
Firebase Cloud Messaging
CI/CD
- Senior Mobile Engineer with 17+ years of experience, focusing on cross-platform mobile application development and SDKs.
- Expertise in various mobile frameworks (Capacitor, React, React Native, Ionic, Flutter) and native (Swift, Objective-C, Kotlin, Java).
- Proficient in CI/CD practices (Fastlane, GitHub Actions, Jenkins), automated deployments, push & messaging tech (APNS, FCM, Courier).
- Strong background in backend and API development, including REST, GraphQL, serverless architectures, along with performance optimization.
- Demonstrated ability in fostering agile methodologies and working with multi-timezone teams to drive project success.
- Holds a BSc in Computer Software Engineering from Sofia University, reflecting a strong technical foundation.
Expert
Sofia, Bulgaria
Dart
Crashlytics
GetX
Software Engineer with over 4 years of specialized experience in Flutter development, proficient in Dart and well-versed in state management techniques including GetX, Provider, BLoC, and Redux. Highly skilled in building scalable mobile applications with robust data management solutions using Firebase, Firestore, and SQLite, while adhering to MVC and MVVM architectural best practices. Successfully developed and deployed 25+ Android and iOS apps to the app stores, implementing real-time authentication and synchronization features. With a solid academic background holding a Bachelor’s in Computer Application and currently pursuing a Master’s in Computer Applications, I bring both strong technical expertise and a continuous learning mindset. Recognized in senior roles at tech firms for leading projects like Surat Jugaad Plus and Pensive, I have consistently demonstrated problem-solving, debugging, and delivering user-centric applications that scale.
Middle
Facebook Auth 3yr.
Dart 3yr.
React
Redux
TypeScript
With an impressive tenure exceeding 15 years in software engineering, the engineer boasts a rich mosaic of technical expertise, underscored by a strong academic foundation with a Doctorate in Mechanical Engineering from the National Technical University of Ukraine 'Kyiv Polytechnic Institute'. Specializing in Flutter, the engineer has a history of crafting mobile applications with a sharp focus on developing new features, debugging, and enhancements. Proven proficiency in a plethora of programming languages and technologies including Dart, React, Redux, TypeScript, and ActionScript is evident. The engineer's versatility is further highlighted by a diverse project portfolio encompassing automotive interfaces, online casinos, educational platforms, and more. Their contribution to software development adheres to the latest SDLC best practices, with applications that have significantly benefited from their knowledge in Data Science and Python, as certified by Robot_dreams.
Expert
Flutter 4yr.
Dart 4yr.
Clean Architecture 4yr.
DartZ 3yr.
Flutter Lifecycle management 3yr.
Flutter Developer with 3+ years of experience delivering high-quality cross-platform apps across fintech, edtech, and
medtech industries. Specialized in Clean Architecture, performance optimization, and offline-first experiences. Proven
ability to own full mobile stacks, from architecture to release, with measurable impact on user engagement and scalability.
Senior
Tashkent, Uzbekistan
Dart 5yr.
Flutter 5yr.
Software engineer with 5+ years of experience specializing in Flutter application development for a variety of industries, including finance, real estate, and governmental disaster management. Demonstrated expertise in both mobile and web development with a solid foundation in computer science, holding a Bachelor's degree in Informatics Engineering. Proficient in key technologies such as Dart (Flutter), React-Native, and Cordova, with a focus on both frontend and backend development. Adept at collaborating in team environments and employing Agile and waterfall methodologies, the engineer has a strong track record in developing applications that address complex requirements. Proficient in state management (BLoC, GetX) and integrating services such as Firebase and RESTful APIs. The candidate brings a combination of technical acumen and practical experience, poised to make a significant impact on future projects.
Middle
South Tangerang, Indonesia
Python
Dart
JavaScript
Figma
Microsoft Visual Studio Code
Software engineer with practical experience in mobile and web development, specializing in Flutter and familiar with state management tools like Provider. Demonstrated expertise in creating user-friendly interfaces and features, as reflected in projects such as a pharmacy management system and a comprehensive food delivery app. Collaborates effectively in agile environments, with a history of successful team-based project completions. Strong foundation in computer science from Jimma University, equipped with skills in Python, Dart, JavaScript, and a range of development tools including Figma, VS Code, and Git. Proficient in the use of Firebase for building scalable apps with real-time data, emphasizing clean code practices and responsive design principles. Proactive in acquiring user feedback to refine product functionality.
Intern
Dart 4yr.
Bloc 4yr.
Crashlytics 4yr.
Senior Software Engineer with a solid 4 years of experience delivering mobile apps, including both the creation of new applications and enhancement of existing solutions. Core competencies involve Flutter development, with strong proficiency in Dart, and experience with various architectural and design patterns. Accomplishments include leading app development for diverse domains such as E-Government, E-Commerce, and FitTech. Technical strengths are underpinned by expertise in memory profiling, performance tuning, implementing authentication mechanisms using JWT, and creating plugins. Skilled in SDLC and software development best practices, with a significant emphasis on distributed tracing techniques to elevate app reliability.
Middle
Tashkent, Uzbekistan
React Native 5yr.
React 5yr.
TypeScript 5yr.
JavaScript 5yr.
Redux 5yr.
Accomplished Software Engineer with 5 years of in-depth experience in mobile and software development primarily focused on React Native, ReactJS, and TypeScript. Demonstrated proficiency in leveraging advanced JavaScript technologies such as Redux and ES6 to build robust mobile applications. Led a technical team and mentored engineers in creating market-centric apps and websites, ensuring adherence to best practices in software development. Key project contributions include the implementation of react-native-firebase for notifications and analytics, and development of complex features for barcode and RFID reader applications. The engineer's academic background in Information Technology fortifies their technical expertise, and a penchant for continuous learning in mobile programming underpins their evolving mastery of the software engineering domain.
Senior
Yerevan, Armenia
React Native
React
JavaScript
TypeScript
HTML/CSS Preprocessors
Accomplished Senior React Native Developer with a solid 7-year track record in mobile application development, underpinned by a bachelor's degree in Computer Science and Engineering. Expert command of React Native, JavaScript, and TypeScript, complemented by proficiency in leveraging ancillary technologies such as Redux, Firebase, and RESTful services. Demonstrated prowess in modern software engineering practices, including unit testing, code reviews, SDLC, and agile methodologies. Adept at fostering junior developers' growth while navigating complex project ecosystems and enhancing app performance and user experience, distinguishing themselves as a potent candidate for technology-driven roles.
Senior
Tashkent, Uzbekistan
NestJS
React Native
React
Experienced full-stack developer with a strong background in scalable architecture design, cloud infrastructure, and modern web and mobile technologies. Proficient in building distributed systems using React Native, React, Node.js, and NestJS. Skilled in managing containerized deployments, service orchestration, and performance optimization across microservice-based environments. Solid understanding of CI/CD pipelines, monitoring, and cloud platforms like DigitalOcean.
Senior
React Native 6yr.
React 1yr.
UI/UX Design
Accomplished Senior Software Engineer with expertise in mobile development, including a leading role in architecting and optimizing a housing support application, ensuring an enhanced user experience. Bring years of experience with a strong focus on ReactJS and React Native across multiple organizations, elevating OPS dashboards, modernizing legacy code, and contributing to a variety of successful app releases. Holds a BSc in Computer Science from the British University in Egypt, marrying technical skills with solid theoretical knowledge. Renowned for implementing new technologies, refining development standards, and delivering high-quality software solutions. Proven capability in the full app lifecycle management and team leadership, aiming to drive efficiency and innovation in software development.
Senior
Riyadh, Saudi Arabia
JavaScript 5yr.
Swift 5yr.
FDD 5yr.
Node.js
React
Software engineer with 9+ years of experience, excelling in full stack development with expertise in JavaScript, Swift, and iOS development. Proven track record of leading successful projects, including winning multiple hackathons and developing robust blockchain-based solutions. Demonstrates strong technical leadership, having managed diverse engineering teams and fostering agile best practices. Well-versed in various technologies like Node.js, React.js, Firebase services, Ethers.js, Web3.js, and AWS, with a solid foundation in computer science from Universidad Nacional del Nordeste. The engineer's proficiency in building scalable systems for music streaming, live video monitoring, and blockchain integration positions them as a valuable asset to any team seeking deep technical expertise and innovative solutions.
Senior
JavaScript 8yr.
TypeScript 6yr.
React 6yr.
React Native 4yr.
Node.js 4yr.
- Experienced in React Native: Developed and delivered multiple React Native mobile applications, including a KenZen App and a Furniture Design Time-Tracking App, integrating Firebase, Redux, animations, and state management. Over 4.5 years of experience with React Native
- Full-Stack Development in Fintech: Led fintech real estate app development, handling both front-end (ReactJS, Styled-Components) and back-end (NodeJS, MongoDB) while managing CI/CD pipelines and real-time updates.
- Senior Developer in Web & Mobile Apps: Designed and implemented scalable mobile and web applications, ensuring high code quality, debugging, and managing releases on App Store and Play Market.
- Developed e-commerce web solutions using Vue and Vuex, collaborating with back-end and QA teams,
- Experienced in Docker, GitHub Actions, and Linux server management, optimizing deployment pipelines and application performance.
- Intermediate English
Senior
Ukraine
React Native
JavaScript
TypeScript
Redux
- Versatile React Native Developer with 5+ years of experience in delivering robust mobile applications, with a deep understanding of the React ecosystem and modern front-end development.
- Holds a solid foundation in software engineering with a Bachelor's degree in Economics, specializing in Accounting and Audit, adding a strong analytical dimension to programming skills.
- Proficient in an array of technologies including JavaScript, TypeScript, ReactJS, Redux, Expo, NodeJS with Express, and associated libraries and tools.
- Demonstrated expertise in the full software development lifecycle (SDLC), object-oriented programming (OOP), Model-View-Controller (MVC) pattern, Test-Driven Development (TDD), and Behavior-Driven Development (BDD).
- Adept in integrating payment solutions such as Stripe, engaging with APIs, and developing cross-platform applications that enhance user experience. Familiar with web development technologies like HTML5, CSS, and cloud services.
- Contributed to diverse projects ranging from live nature cams, NFT galleries, healthcare, e-commerce, to social media marketing, demonstrating versatility and the ability to adapt to varied domains.
- Team player with intermediate English communication skills, facilitating collaboration with global teams and ensuring alignment with project goals.
Senior
Uzhgorod, Ukraine