I develop high-performance hybrid mobile applications that deliver reliable results in real-world environments, including Firebase integrations, push notifications, custom native plugins, and complex SDK integrations.
With 14+ years of experience and over 200 successfully delivered projects, I specialize in building, optimizing, and maintaining Android and iOS applications using Ionic, Cordova, Capacitor, Vue.js, and React Native.
I help businesses launch scalable, cost-effective mobile solutions and solve critical issues that other developers struggle to fix. My expertise includes app stabilization, performance optimization, native SDK integration, App Store compliance, and troubleshooting complex mobile application challenges.
### What I Can Do for You
✔ Develop cross-platform mobile applications (Android & iOS) from scratch
✔ Convert existing websites or web applications into mobile apps
✔ Develop custom Cordova and Capacitor plugins
✔ Integrate native iOS and Android SDKs into Ionic applications
✔ Diagnose and resolve crashes, bugs, and performance bottlenecks
✔ Upgrade legacy applications (Cordova → Capacitor migration)
✔ Integrate APIs, Firebase services, and third-party platforms
✔ Resolve App Store and Google Play review and deployment issues
✔ Optimize application speed, stability, and user experience
### Technical Expertise
• Ionic Framework (Angular & Vue)
• Apache Cordova & Capacitor
• Vue.js & React Native
• JavaScript, TypeScript, HTML5, CSS3
• Native Android (Java/Kotlin)
• Native iOS (Swift/Objective-C)
• Firebase (Authentication, Firestore, Analytics, Push Notifications)
• REST APIs & Third-Party Integrations
• WebView Optimization & Plugin Debugging
### Specialized SDK & Plugin Development
• Custom Cordova Plugin Development
• Custom Capacitor Plugin Development
• Native SDK Bridging for Ionic Applications
• Microblink BlinkID Integration
• Passport, Driver's License & ID Card Scanning
• Selfie Verification & Face Matching
• OCR & Document Data Extraction
• Barcode & QR Code Scanning
• Camera & Media Processing Integrations
• Biometric Authentication
• Payment Gateway SDK Integrations
• Push Notification SDK Integrations
One of my key specialties is developing custom native plugins for Ionic, Cordova, and Capacitor applications. I have successfully built and integrated complex SDKs, including Microblink BlinkID, enabling passport scanning, driver's license scanning, ID card recognition, selfie matching, and OCR-based data extraction on both Android and iOS.
When a required SDK does not have an existing plugin, I can build the complete native bridge and integration from scratch.
### Why Clients Work With Me
• Strong expertise in solving complex mobile application issues
• Advanced debugging skills across native and hybrid environments
• Extensive experience with plugin development and SDK integrations
• Clear communication and reliable delivery
• Proven track record with production-grade and long-term projects
If your application is experiencing crashes, performance issues, SDK integration challenges, App Store rejections, or deployment problems, I can quickly identify the root cause and implement a reliable solution.
From concept → development → deployment → scaling, I manage the complete mobile application lifecycle.
Available to start immediately.
Hybrid App Development
Apache Cordova
Cross-Device Compatibility
Mobile App Development
Mobile App Bug Fix
API Integration
iOS Development
Android App
REST API
Firebase
SQL
React Native
Flutter
App Store Upload
Back-End Development
UX & UI
App Design
Apple Xcode
TestFlight
JavaScript
Khubchand B.
Mathura, India
$12/hr
5.0
17 jobs
I’m a Mobile App Developer with hands-on experience building and publishing production-ready apps for both iOS and Android — from initial development to final App Store and Play Store submission.
I specialize in turning ideas or existing web apps into fully functional mobile applications, handling everything end-to-end including authentication, payments, push notifications, and backend integrations.
🚀 What I Do
📱 Build and publish mobile apps (iOS & Android)
🔄 Convert web apps into native apps using Capacitor
🔐 Implement secure authentication (Firebase, Google, Facebook, LINE, Apple, Phone OTP)
💳 Integrate payments (Stripe, 3D Secure, custom flows)
🔔 Set up push notifications using Firebase
☁️ Full Firebase integration (Auth, Firestore, Functions, Storage)
🎬 FFmpeg-based video & audio processing tools
💡 Mobile Development Expertise
Capacitor & Cordova (custom plugins, native integrations)
Native iOS (Objective-C) & Android (Java)
Ionic, Angular, Vue (Quasar)
REST API & backend integrations
I ensure apps are:
✔ Stable and production-ready
✔ Fully compliant with App Store & Play Store guidelines
✔ Optimized for performance and scalability
🎯 Real Experience
Built and published cross-platform apps from scratch
Implemented multiple authentication systems across apps
Integrated secure payment flows including Stripe
Developed FFmpeg-based tools for video/audio processing
Delivered apps with real users and production usage
🤝 Why Work With Me
Clear communication and fast response
Focus on long-term, scalable solutions
Experience handling complete app lifecycle (dev → publish → maintain)
Reliable delivery with attention to detail
If you’re looking for someone who can take your app from idea to live on the App Store/Play Store, I can help you build it the right way.
Android App Development
iOS Development
App Store Upload
Publishing
Web Application
Firebase
Google Cloud Platform
User Authentication
Quasar Framework
Vue.js
TypeScript
FFmpeg
Flutter
React
T Vinh N.
Da Nang, Vietnam
$20/hr
5.0
6 jobs
I'm a Web and Mobile App Engineer with over 12 years of experience, including over 7 years in developing high-quality iOS, Android, and cross-platform applications using Flutter.
Good at Flutter, Dart, PHP, JavaScript, HTML5, CSS3, NodeJS, ReactJS, Python, TensorFlow
Can learn about new technology relatively quickly
Have experience in the position of Team Lead
Languages: Flutter, Dart, objective C, C, C++, android, Python, PHP, SQL, HTML/CSS, JavaScript, C#, NodeJS, ReactJS
Databases: Isar, MySQL, SQLite, Firebase Databases, MongoDB
Web Technologies: Apache, Nginx, DirectAdmin, Npm
Design Tools: Figma, Adobe Photoshop
Cloud Developer Tools: GCP, AWS, Azure, Appwrite
Technologies/Frameworks: Docker, Centos, VMware, GitHub, Firebase
Dart
Flutter
C#
Firebase
SQLite
Mobile Development Framework
Mobile App
Google Cloud Platform
Microsoft Azure
Amazon EC2
Postman
RESTful API
NoSQL Database
Material Design
Model View ViewModel
Gustavo L.
Goiania, Brazil
$30/hr
5.0
2 jobs
Mechatronics Engineer and Software Developer with 6 years of experience in developing cutting-edge technology solutions. Skilled in programming and mobile app development, specializing in React, NextJs, React-Native and Android. Proficient in frontend mobile app development, creating sleek, user-friendly interfaces. Experienced in full-stack development using Node.js for the backend, with expertise in React, NextJs, Redux, Typescript, GraphQL, and React Query. Passionate about engineering and technology, continuously seeking new challenges and opportunities for growth. Worked on projects for major companies in Europe and America, delivering innovative solutions. Strong problem-solving and communication skills. Industries: Technology, Engineering, and Software Development.
MY PORTFOLIO ONLY SHOWCASES PERSONAL SIDE PROJECTS, I ALSO HAVE EXTENSIVE COMMERCIAL EXPERIENCE, INCLUDING WITH BIG US TOP COMPANIES.
React | NextJs | T3Stack | React Native | Redux | Typescript | GraphQL| React Query | Native Android
React Native
React
Node.js
Android App Development
TypeScript
Android Studio
Redux
Next.js
Git
Redux Thunk
Redux Form
Redux Saga
JetPack
Cypress
ExpressJS
Hai N.
Hanoi, Vietnam
$12/hr
5.0
7 jobs
Senior Mobile Application Developer | Flutter, Android, iOS | SAP, AI & Enterprise Integration
I am a Senior Mobile Application Developer with 10+ years of experience delivering production-ready applications across Android Native, iOS, Flutter, and React Native, along with 3 years of experience working with SAP systems.
My strongest expertise is in Android (Java & Kotlin), focusing on performance optimization, scalable architecture, and system-level development. I have also delivered multiple Flutter applications, helping teams accelerate development while maintaining high code quality.
🔹 SAP & Enterprise Experience (3 years)
Hands-on experience with SAP ABAP (custom reports, data processing, backend logic)
Experience working with SAP Fiori / UI5 for enterprise user interfaces
Functional knowledge of SAP modules: SD, MM, FI and related business workflows
Integration between mobile applications and SAP systems via APIs / OData services
Handling enterprise data flows, transactions, and secure system communication
🔹 AI & AI Agent Integration
Integrating AI APIs (chatbots, content generation, automation tools) into mobile apps
Building AI-powered features such as smart assistants and workflow automation
Working with AI agents for task execution and structured responses
Managing prompt design, API communication, and response handling
I specialize in:
🔸 Building and improving existing mobile applications
🔸 Bug fixing, performance optimization, and feature enhancements
🔸 Clean architecture (MVP, MVVM) for scalability
🔸 Complex integrations (AI systems, SAP, enterprise backends)
After several years as a hands-on developer, I became a Team Leader, responsible for architecture decisions, code reviews, and mentoring developers.
Flutter
Android
Java
Kotlin
Mobile App Development
Dart
Mobile App Bug Fix
Bug Fix
App Feature Development
App Development
In-App Subscription
Android App Development
AI App Development
SnapKit
SAP Fiori
ABAP
SAP SD
SAPUI5
AI Mobile App Development
Web & Mobile Design Consultation
Marina A.
Sao Paulo, Brazil
$20/hr
5.0
6 jobs
Software Engineer specializing in cross-platform mobile development with Flutter, alongside native iOS (Swift) and Android (Kotlin) experience. I help businesses build, improve, and maintain high-quality mobile applications—from implementing new features and fixing complex bugs to optimizing performance and modernizing legacy codebases.
I focus on writing clean, maintainable code, creating intuitive user experiences, and delivering reliable solutions on time. Whether joining an existing project or building new functionality, I adapt quickly, communicate clearly, and work collaboratively to ensure successful releases.
Mobile Development Framework
Flutter
Dart
Swift
Kotlin
Mobile App Development
Mobile App Improvement
iOS Development
iOS
Android
Android App
Android App Development
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At A Glance: Appcelerator Titanium
Appcelerator Titanium is one of the most trusted and reliable tools for businesses everywhere to create and manage mobile applications. One of its most appealing aspects as an open-source framework is its ability to develop apps that function on multiple platforms, reaching every kind of audience whether they prefer Android, iOS, Windows, or another device. However, you may not have the education, skills, and experience to manage this framework yourself, or perhaps the demands of your business restrain your available time. The Appcelerator Titanium specialists on Upwork offer just the solution you need, allowing you to entrust this task to their capable hands and remove the burden from your shoulders.
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