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I already run a live crypto-exchange and all core services are exposed through a documented REST/WebSocket API. What I now need is a polished native (or cross-platform) mobile application that talks directly to those existing endpoints, giving my users a fast, secure and intuitive on-the-go trading experience. Here’s the scope as I see it: • Interface & UX Design and build a modern, brand-consistent interface that feels at home on both iOS and Android. I will supply logos, colour palette and wireframes for the key screens; you’re free to refine the micro-interactions and visual polish. • API Integration Hook every screen into the current API layer—account creation/login, balance retrieval, order book streaming, trade execution, deposits/withdrawals, and basic settings. I’ll provide a Postman collection, test keys and a staging server for verification. • Security & Auth Implement a secure authentication flow using my existing token system; the app must store nothing sensitive in plain text. Two-factor and biometric unlock are already supported by the API and should be surfaced to the user. • Notifications Push or in-app notifications for order fills, price alerts and system messages. • Testing & Delivery Send regular TestFlight / Google Play Console builds, fix bugs quickly and hand over all source code, build scripts and lightweight documentation so my internal team can maintain future versions. I want clean, well-commented code, adherence to best practices (Swift/Kotlin or React Native/Flutter—open to your recommendation) and a timeline we can both commit to. If you have genuine crypto or fintech app experience, do highlight it when you respond.
Project ID: 40607103
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Hello We are Ominfowave Software Services Pvt. Ltd., and we have an expert mobile application development team with 10+ years of experience in building reliable, high-quality apps. ? Our Core Expertise •Android App Development (Kotlin / Native) •iOS App Development •Flutter & FlutterFlow (Cross-platform) Our team understands not just development, but also performance, user experience, scalability, and timely delivery. ? What We Can Deliver ✔ Social media integrations (Facebook, Google, Twitter, etc.) ✔ Google APIs (Maps, Places, FCM, YouTube, Analytics) ✔ Offline & cloud database solutions (SQLite, MySQL, Realtime DB) ✔ Secure payment integrations (Stripe, PayPal, Braintree) ✔ Ad monetization (AdMob, Appodeal, MobVista) ✔ In-App Purchases ✔ Location tracking & real-time features ✔ Chat & messaging applications ? App Types We’ve Built •Social Media Apps •Shopping & eCommerce Apps •Job Portals •Taxi / Carpooling Apps •VPN & Utility Apps •Travel & Booking Apps •Live Streaming Apps •AI & Machine Learning–based Apps ? Why Work With Us •10+ years of hands-on experience •Clean, scalable & secure code • Clear communication & regular updates • On-time delivery with quality assurance • Long-term support after project completion We would love to work with you and build a long-term, trusted business relationship. Let’s discuss your idea and turn it into a successful application Warm regards, Vishal Nasit Ominfowave Software Services Pvt. Ltd.
$3,000 USD in 30 days
8.4
8.4

With over a decade of experience in native and cross-platform mobile app development, I understand the importance of creating a polished and user-friendly Crypto Exchange Mobile App for your existing crypto-exchange services. My background in high-security FinTech systems directly aligns with the challenges of providing a fast, secure, and intuitive trading experience for your users on-the-go. To ensure scalability and security, my strategic insight would be to implement a robust authentication flow and encryption methods to store sensitive data securely. In a similar project, I successfully built and scaled a Telegram Mini App serving over 1 million users, showcasing my ability to handle high complexity and user volume effectively. I am confident in my ability to design and build a modern interface, integrate with your existing API, implement necessary security measures, and provide timely testing and delivery. I am open to using Swift/Kotlin or React Native/Flutter based on your recommendation to deliver a high-quality app within the specified budget and timeline. Let's discuss further to create a roadmap for your project's success.
$4,000 USD in 45 days
8.4
8.4

✅ Crypto Exchange App| React Native | Firebase |Mobile App Development Expert Hi, Hope you are doing good. I have read your requirements carefully and can give you 100% assistance as a React Native Developer for building or enhancing your mobile application. I specialize in creating fast, stable, and scalable apps for both iOS & Android, backed by a secure and efficient Firebase architecture. I’d love the opportunity to discuss your idea further and collaborate on developing a modern, intuitive, and impactful app. (Note: Please consider the current budget as flexible — we can finalize it after discussing the complete scope.) Thanks & Regards, Kajal
$4,000 USD in 7 days
7.3
7.3

This looks like a great fit, Hi, I will deliver a polished crypto trading app for iOS and Android that connects to your existing REST/WebSocket API, covering order book streaming, trade execution, deposit/withdrawal flows, and biometric/2FA unlock. I will use Flutter for a single codebase with near native performance. On a recent fintech app, wiring the order book via WebSocket directly into a diff based list widget kept the UI responsive even during high volume market events. I will apply the same approach to your exchange feed. Questions: 1) Are the wireframes you mentioned already in Figma or another tool, or will you share static files? 2) For push notifications (order fills, price alerts), do you already have a Firebase project set up, or should I provision that? Ready to start whenever you are. Kamran
$3,361 USD in 30 days
7.6
7.6

Hi, Your exchange already has the hard part in place with a documented API. The real challenge is turning those services into a mobile experience that feels fast reliable and secure while handling live market data without sacrificing performance. The authentication flow notifications and real time trading all need to work seamlessly because even small delays affect user trust. I can build a clean and scalable mobile app that connects directly to your existing REST and WebSocket APIs while following mobile best practices. From secure authentication and biometric login to live order books trading deposits withdrawals and push notifications every feature will be built around stability maintainability and a smooth user experience with regular test builds throughout development. One decision will influence the long term roadmap. Are you leaning toward Flutter or React Native for shared code or would you prefer fully native apps for maximum performance?? NOTE: Lets start immediately and get visible results not theory. My portfolios freelancer.pk/u/Hammadhassan21 If you find my offer satisfactory, we will be happy to discuss your project in detail. Best regards, Hammad H..
$3,000 USD in 20 days
7.3
7.3

Hi, I get how important it is for your app to be quick and secure while keeping users happy. I’ve worked on projects like a sports app and a multi-vendor marketplace that needed smooth UI and safe login flows. I will connect your app directly to your existing API, making sure login, trading, and notifications work well. Do you want me to also help optimize micro-interactions for better user flow? Let’s chat to make a detailed plan and build an impressive app together. Regards, Nick.
$3,000 USD in 18 days
7.0
7.0

Hi there, I’ve reviewed your Flutter app requirements and would love to help. With 5+ years of experience in cross-platform development, I specialise in clean UI, smooth performance, and robust API integration. I’ll begin with clear planning, share regular progress updates, and ensure the app is fully tested before launch. Let’s connect to discuss your vision — I’m ready to get started! Best, Bhargav Flutter Developer | Android & iOS Expert
$3,000 USD in 7 days
7.0
7.0

Hi, I have extensive experience building crypto, fintech, and trading applications with secure API integrations. I can develop your mobile app in Flutter, giving you a single high-performance codebase for both iOS and Android while maintaining a native user experience. The app will include: Modern, responsive UI matching your brand and wireframes. Full integration with your REST/WebSocket APIs for authentication, balances, live order books, trading, deposits, withdrawals, and account settings. Secure token storage using Keychain/Keystore, biometric login, and 2FA support. Real-time market updates and push notifications for order execution, price alerts, and system messages. Regular TestFlight and Google Play builds, comprehensive testing, complete source code, and deployment documentation. I've worked with blockchain platforms, crypto wallets, payment gateways, and real-time trading systems, so I'm familiar with WebSocket streaming, secure authentication, and performance optimization for financial applications. Please share your API documentation, Postman collection, and staging environment. I'll review the endpoints and provide a detailed implementation plan, timeline, and accurate estimate. I look forward to working with you!
$4,000 USD in 30 days
6.8
6.8

Hi, It will be an honor for me to work with you. I have got 12 years of mobile application development experience (iOS, android, flutter and react native). Lets discuss this in detail and get this started. Looking forward to hear from you.
$3,500 USD in 30 days
6.9
6.9

Hi I will be able to help you. Please message me so that we will have detail technical discussion. I have 9+ years of combined experience in Mobile Application development, Website development, Desktop application development, 3rd party Artificial Intelligence api, AR/ VR, Chatbot, Blockchain- Cryptocurrency, CRM & ERP, Game Development and any other Software development. I am having expertise in Native on Android Java, kotlin and IOS Swift, and For Hybrid Cross platform on Flutter Dart & React- Native, and for web and backend on react js and node js, Python Django. Please consider me and initiate a chat for further detailed discussion. Regards, Anju
$3,000 USD in 45 days
6.6
6.6

Hi there, Hope you are doing well I'd love to help build your Crypto Exchange Mobile App. Our team has extensive experience developing secure FinTech and trading applications, integrating REST/WebSocket APIs, real-time market data, authentication, and high-performance mobile apps. Why We're a Good Fit Experience building crypto, fintech, and trading platforms Expertise in Flutter for cross-platform iOS & Android development Strong knowledge of REST & WebSocket API integration Secure authentication with JWT, 2FA, and biometric login Clean, scalable architecture with well-documented source code Recommended Tech Stack Mobile: Flutter Backend Integration: Existing REST & WebSocket APIs Authentication: JWT, 2FA & Biometric Login Notifications: Firebase Cloud Messaging (FCM) Local Storage: Secure Storage (Encrypted) Architecture: Clean Architecture with BLoC/Provider What We'll Deliver Production-ready iOS & Android applications Complete integration with your existing exchange APIs Real-time order book, balances, trading, deposits & withdrawals Secure login, biometric authentication & push notifications Complete source code, documentation, testing, and App Store/Google Play deployment support We're confident we can deliver a secure, high-performance trading app with an excellent user experience and long-term scalability. Looking forward to working with you. Thanks & Regards, Dheeraj K.
$3,000 USD in 25 days
7.0
7.0

Hello! As per your project post, you are looking to build an Crypto Exchange Mobile App for your existing cryptocurrency exchange platform by connecting with your documented REST and WebSocket APIs. The application should provide users with a seamless trading experience across iOS and Android, including account management, real time market data, order execution, deposits, withdrawals, security features, and notifications. My approach would begin with understanding your existing API architecture and designing a polished mobile experience aligned with your brand identity. I will integrate authentication, user profiles, wallet balances, live order books, trading workflows, transaction history, deposits and withdrawals, and account settings through your existing endpoints. I specialize in Flutter, React Native, Swift, Kotlin, REST API integration, WebSocket implementation, fintech applications, blockchain platforms, secure authentication, and high performance mobile solutions. My focus is on delivering a reliable trading application with strong security practices, smooth user experience, and scalable architecture suitable for a growing crypto ecosystem. Let's connect to discuss your requirements and build a secure mobile trading experience for your crypto exchange users. Best regards, Nikita Gupta
$3,000 USD in 45 days
5.7
5.7

Hi, I've carefully reviewed your requirements and understand that your crypto exchange backend is already live with REST and WebSocket APIs. The objective is to build a secure, high-performance mobile application that connects directly to your existing services, delivering a smooth trading experience without changing the backend architecture. I recommend Flutter for a single codebase that delivers native performance on both iOS and Android while simplifying long-term maintenance. The app will integrate secure token authentication, biometric login, 2FA, WebSocket streaming, push notifications, and encrypted local storage. Working Flow → Review API documentation, authentication, and WebSocket events → Develop UI from your wireframes and branding → Integrate trading, wallet, deposits, withdrawals, and account APIs → Implement real-time order books, notifications, biometrics, and security → QA, TestFlight & Play Console releases, optimization, and deployment The code will follow clean architecture, be well documented, and be easy for your internal team to maintain and extend. ✔ 2 Years Free Support ✔ Complete Source Code & Build Files ✔ Daily Progress Updates I'd love to help build a reliable, scalable mobile trading app that integrates seamlessly with your existing exchange. Thanks, InvokeTech
$3,000 USD in 25 days
5.6
5.6

Hello, you already have the hard part in place—a live exchange with documented REST/WebSocket endpoints—so the mobile app is mainly an execution problem around state, security, and responsiveness. The real engineering risk is keeping trading state consistent under reconnects, partial updates, and auth-sensitive actions like execution and withdrawals. I've built several production systems with real-time streaming behavior and secure client/server coordination, including WebSocket-driven flows and API-first products that had to remain stable under live usage. The closest references are AI Translator Plugin for low-latency streaming/session handling and Enterprise ProxyTool Client App for secure client architecture and backend synchronization. Both required careful treatment of live state, failure recovery, and maintainable handoff. I usually structure systems like this around separate layers for auth/session state, market data streaming, trading actions, and notification handling so reconnect logic and sensitive operations do not bleed into UI concerns. With a trading app, that separation matters more than the framework choice. I’d want to review how your order book stream handles replay, how token refresh interacts with WebSocket sessions, and how 2FA/biometric flows are enforced during high-risk actions. If useful, I can sketch the client state model for streaming, execution, and secure auth handoff against your staging API. Clifton
$4,000 USD in 7 days
5.6
5.6

Hi, I can help you build a polished mobile app that sits seamlessly on top of your existing exchange APIs, so there's no need to rebuild any backend logic. I'll focus on smooth REST/WebSocket integration, real-time market updates without unnecessary refreshes, secure authentication with encrypted token storage, biometric login, and a responsive trading experience. A few quick questions: How frequently does the order book update over WebSockets? Are there any API rate limits or concurrency limits I should optimize for? Will the staging environment include all trading and notification features for testing? I have experience building Flutter applications with REST APIs, WebSockets, secure authentication, and real-time data, ensuring performance, security, and clean, maintainable code. Looking forward to discussing the details.
$4,000 USD in 7 days
5.5
5.5

Hello, Your crypto exchange mobile app is a great match for my experience. I have strong experience with mobile and web development, REST and WebSocket APIs, secure authentication, real time data, and software that supports growing user bases. I can quickly understand your existing API structure, connect the required trading features, and deliver exactly what your users need across iOS and Android. I can also work with staging environments, testing workflows, push notifications, and secure token handling. I would love to have a quick call or meeting to understand your goals clearly and make sure I am aligned with your expectations from the start. I will share my portfolio in chat I look forward to hear from you. Thanks Best Regards, Mughira
$4,000 USD in 7 days
5.2
5.2

As a seasoned Full Stack Developer, I bring over 8 years of experience in mobile app development. My skills span across Android, Flutter, and React Native, all of which align with your preferred technology stack. In addition, I have a strong passion for creating polished interfaces and memorable user experiences that are secure and adhere to industry best practices - qualities you need for a successful crypto exchange mobile app. \ Moreover, as a believer in long-term support and solution scalability, I assure you that my assistance won't end with just delivering the final product. I offer continual support, periodic updates, and ready availability for any future changes or upgrades you may require. Partnering with me not only gets you a developer but a reliable collaborator who will remain dedicated to turning your vision into reality while ensuring its continued success even post-launch.
$3,001 USD in 15 days
5.0
5.0

Building a professional, intuitive and secure crypto exchange app that aligns with your brand image is something I am confident I can excel at. Over the last 5 years, I have honed my skills as a Full Stack Web and Mobile App Developer by working on a variety of projects, including both B2B and B2C platforms. This means I understand what it takes to design a user-friendly interface that integrates seamlessly with solid backend architecture for APIs, security, order execution and notifications. I have extensive experience in mobile app development using both React Native and Flutter which gives me the versatility you might be looking for. Comfortable with agile project management methodologies, I provide regular updates via TestFlight & Google Play Console builds and am quick to address any bugs before delivering the project to ensure your team can easily manage future versions with my lightweight documentation and code. What sets me apart is my commitment to providing end-to-end development support. Whether that's collaborating with your team to bring your vision to life or suggesting improvements based on crypto and fintech-specific knowledge, I approach every project with dedication to creating impeccable solutions. I look forward to discussing your project in more detail and working together to create an amazing experience for your users.
$4,000 USD in 7 days
4.9
4.9

I understand you need a performant, native mobile application to connect directly to your existing crypto exchange API, providing users with a seamless on-the-go trading experience. My recent work on a high-frequency trading dashboard for a fintech startup, which involved direct WebSocket integration for real-time data streams and low-latency order execution, directly aligns with your requirement for speed and responsiveness. My approach will leverage Flutter for cross-platform development, enabling a single codebase for both iOS and Android while maintaining native performance. We'll establish robust WebSocket connections for real-time price updates and order book synchronization, and utilize efficient REST calls for all other operations. Data will be securely stored locally using SQLite for offline access and fast retrieval. I'll implement a state management solution like Provider or Riverpod for predictable UI updates and integrate a secure authentication flow mirroring your API's requirements. Have you considered how user session management will be handled for security and convenience across multiple devices? Additionally, what are your priorities regarding push notifications for price alerts or order status updates? I'm eager to discuss how we can translate your robust API into a best-in-class mobile trading experience.
$4,233 USD in 21 days
4.7
4.7

Best regards, Waqas & GoDesign Team
$3,000 USD in 3 days
4.5
4.5

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