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Job Title: Senior Full-Stack App Developer for Debugging, UX Fixes, and Stability Improvements Job Description: I’m looking for an experienced full-stack developer to review and refine an existing mobile/web application that is already built and functional but needs polishing and technical corrections. The goal is to identify and resolve smaller issues that affect user experience, logic flow, and overall stability. This is not a project from scratch. The application is operational, but it requires a developer who can carefully audit the system, locate inconsistencies, and implement clean fixes. Responsibilities include: Reviewing existing frontend and backend logic Fixing UI/UX inconsistencies and interaction bugs Ensuring user actions trigger the correct outcomes across the platform Improving state management and data rendering reliability Identifying inefficiencies or fragile areas in the code Ensuring the application behaves consistently across core user flows Maintaining existing architecture while making targeted improvements Ideal candidate: Strong experience with modern full-stack development Comfortable jumping into existing codebases Detail-oriented and capable of identifying subtle logic or UI issues Able to document fixes and explain improvements clearly Experience improving production apps is preferred Project Scope: This will begin as a code and functionality audit followed by targeted fixes. If the collaboration goes well, there may be opportunities for ongoing development and feature improvements. Please include: Relevant projects or apps you’ve improved/debugged Your experience working with existing production codebases Your approach to auditing and stabilizing applications Looking for someone who can quickly understand a system, diagnose problems, and implement clean solutions.
Project ID: 40281564
155 proposals
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Active 2 mos ago
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155 freelancers are bidding on average $52 USD/hour for this job

⭕⭕ FULL STACK DEVELOPER ⭕⭕ Hi there, ✔️ I see you are looking for an experienced developer to audit, refine, and stabilize your existing application. I’d be happy to review the current codebase, identify inconsistencies, and implement clean fixes to improve performance, reliability, and overall user experience. ✍️ Which tech stack/frameworks is the application currently built with? ✍️ Do you already have a list of known issues, or would you prefer a full technical audit first? ➰ I’m comfortable jumping into existing production codebases, diagnosing problems quickly, and implementing clean, well-documented fixes. Looking forward to collaborating and helping make your application more stable and polished. Thank you.
$50 USD in 40 days
10.0
10.0

Hello Good Day, With an extensive portfolio that includes successfully improving and debugging a range of complex web and mobile applications, I am ready to bring my expertise to your project. My name is Rinsad Ahamed, and I lead a highly skilled team that specializes in Full Stack Development, JavaScript, Mobile App Development, PHP, Web Development, and Website Design - all of which are directly applicable to the task at hand. We understand the critical nature of precise code auditing and clean fixes in existing applications. Our approach involves a careful analysis of both frontend and backend logic in order to identify any inconsistencies or inefficiencies. We are meticulous when it comes to fixing UI/UX anomalies and also adept at maintaining existing architecture while making targeted improvements. We document all the solutions identifed efficiently and transparently, ensuring you are always aware of the changes being made. In conclusion, our emphasis is not just on swift delivery but on delivering measurable outcomes which is core to your requirement. We do this by combining the latest AI-powered automation with clean architecture for scalable and resilient digital solutions ensuring your application behaves consistently across core user flows. Looking forward to working with you Kind regards Rinsad
$50 USD in 40 days
9.8
9.8

As a seasoned full-stack developer with extensive experience in auditing existing codebases and improving production applications, I'm confident that my skills align perfectly with your project needs. Whether it's fixing UI/UX inconsistencies, ensuring logical flow or maintaining architecture while implementing improvements, I've got you covered. At ZAWN Tech, we understand the importance of stability, reliability and user experience for an application that is already operational. With this in mind, we conduct thorough audits to locate even the most subtle issues and implement clean fixes. Our track record includes many successful projects involving web and mobile app debugging and improvement. Furthermore, our ability to quickly understand a system, diagnose problems and apply targeted solutions has earned us 200+ recommendations over the last decade. Working with ZAWN Tech means not just getting the job done but receiving long-term support for any future enhancements as well. Choose us for a result-driven collaboration that will elevate your app to its highest potential.
$50 USD in 40 days
9.5
9.5

Hello! Your project is clear: the application is already functional, and what you need now is a careful audit followed by targeted fixes to improve stability, UX consistency, and logic flow. Understanding You are looking for someone who can: • Review the existing frontend and backend logic • Identify and fix UI/UX inconsistencies and interaction bugs • Ensure user actions trigger the correct outcomes across the platform • Improve state management and data rendering reliability • Detect fragile areas in the code and implement clean, maintainable fixes Approach I typically start with a structured audit: • Review core user flows and reproduce reported issues • Analyze state management, API calls, and UI rendering behavior • Identify logic inconsistencies or inefficient patterns • Document findings and implement targeted fixes without disrupting the current architecture What You’ll Receive • Clean fixes for UI/UX and logic issues • Improved stability across core user flows • Notes explaining the changes and improvements made • Recommendations for future optimization if needed I’m comfortable jumping into existing production codebases, quickly understanding system structure, and delivering focused improvements. Best regards, Jasmin
$50 USD in 40 days
9.5
9.5

Greetings from Logictrix! My name is Jas, and I am looking forward to discuss about your app in details over the Chat or Call. We have enough app developers available in team so I can assure you to deliver this project at a fairly low cost with great quality and with a commitment for long term support. *** We have now earned 'Expertise' level in AI, ChatGpt and a couple of other AI platforms for App development and other Chatbot work! *** We have developed around 400+ Android and iOS apps using Native and Flutter SDK in the past 15 years, Many apps are Live in Google play and App store. We will share our detailed portfolio over the Chat once we connect. Looking forward to your reply... Thanks and Regards Jas
$50 USD in 40 days
9.6
9.6

With over a decade of experience in full-stack development across various platforms, I understand the importance of refining and improving existing applications for seamless user experience. Your project requirement for a Senior Full-Stack App Developer to enhance the functionality, UX, and stability of your mobile/web application resonates with my expertise. I have successfully worked on similar projects in the past, where I audited existing codebases, fixed UI/UX inconsistencies, and improved data rendering reliability to enhance overall performance. My approach involves meticulously reviewing frontend and backend logic, identifying inefficiencies, and implementing clean fixes to ensure consistent user actions and outcomes. In the realm of app improvement and debugging, I have a proven track record of delivering results for clients in fintech, eCommerce, and health sectors. By quickly understanding systems, diagnosing issues, and implementing solutions, I can help elevate your application to its full potential. Let's collaborate to audit and refine your app, paving the way for ongoing development and feature enhancements. Feel free to reach out to discuss how I can add value to your project.
$50 USD in 15 days
9.2
9.2

With your existing application in need of fine-tuning, there are few teams as equipped as ours at CnELIndia to get the job done. Our longstanding prowess in both frontend and backend development gives us a knack for diving into existing codebases and swiftly identifying any hiccups. Over the years, we have successfully improved and debugged numerous applications - our expansive portfolio and multitude of glowing testimonials stand as testament to that fact. At CnELIndia, we don’t just fix issues, we enhance user experiences too. We take a meticulous approach to auditing applications and collaborate closely with the client to garner a comprehensive understanding of how the system functions, ensuring all identified problems are resolved consistently across all core user flows. Moreover, our proficiency in handling PHP, WordPress, WooCommerceett., and above all, React Native - a stack your project currently uses -positions us prominently for this task. So why hire us? Because with over 18 years of experience, we are adept at diving into existing systems and emerged equipped with a keen eye for detail necessary to identify even the subtlest of bugs or issues that affect UX and stability. With us on board you can expect meticulous work, efficient fixes and if successful collaboration persists after this task is completed - ongoing development should it be required.
$50 USD in 40 days
9.1
9.1

Hi there, I will audit your existing application, identify UI/UX inconsistencies and logic flow issues, and implement targeted fixes that improve stability without disrupting your current architecture. This covers frontend rendering problems, backend logic corrections, state management reliability, and ensuring user actions produce the correct outcomes across all core flows. My approach starts with tracing each major user flow end-to-end, logging where state updates fail silently or where the UI falls out of sync with backend responses. This catches the subtle bugs that surface only under specific conditions - the kind that standard testing often misses but real users hit regularly. I will document every fix with clear explanations so your team has full visibility into what changed and why, making future maintenance easier. Questions: 1) What is the current tech stack on both frontend and backend? 2) Are there specific user flows or screens where the issues are most noticeable right now? Looking forward to discussing further. Thanks and best regards, Kamran
$50 USD in 40 days
8.5
8.5

Hello, Your project description stood out because it focuses on improving and stabilizing an existing application rather than rebuilding it from scratch. I have extensive experience stepping into production systems, auditing the codebase, and implementing targeted fixes that improve reliability, UX consistency, and system stability. I’m very comfortable working with existing codebases and quickly understanding system structure, which allows me to identify subtle issues that often affect user experience and application stability. If helpful, I can begin with a structured system audit and produce a clear list of issues and recommended fixes before implementing improvements. I’d be happy to review the current stack and repository structure to determine the fastest path to stabilizing the platform. Looking forward to hearing more about the application. Best regards. ADEEL
$50 USD in 40 days
8.1
8.1

Hi, I’m experienced in stepping into existing production codebases and stabilizing them without disrupting the current architecture. From your description, it sounds like the main need is a careful audit of both frontend and backend logic to identify fragile areas affecting UX flow, state handling, and overall reliability. My typical approach is to first review the codebase and core user flows, isolate inconsistencies in logic or UI behavior, and then implement targeted fixes that improve stability while keeping the system maintainable. I also document the changes clearly so your team understands what was adjusted and why. I’d be happy to review the application and outline the most impactful fixes to improve stability and user experience. Best,
$55 USD in 40 days
7.9
7.9

Hello I hope you're doing well I will review and refine your existing mobile and web application to fix UI and UX issues, improve stability, and ensure consistent user flows. I will audit both frontend and backend logic, identify fragile areas or inefficiencies, and implement clean well documented fixes without altering your existing architecture. My approach focuses on detail oriented code inspection, testing key user interactions, and improving state management and data rendering reliability. I have experience working with production apps, debugging complex systems, and optimizing applications for smooth, predictable behavior across all core flows. You will receive a polished, stable app with documented improvements ready for ongoing enhancements if needed. Kindly take a moment to review my portfolios, https://www.freelancer.com/u/Hammadhassan21 If you find my offer satisfactory, we will be happy to discuss your project in detail. Best Regards Hammad Hassan
$50 USD in 40 days
7.9
7.9

Hello, I understand that you need a seasoned full-stack developer to audit your existing mobile/web application, resolve UI/UX inconsistencies, and strengthen its overall stability. I specialize in diving into production codebases, quickly diagnosing subtle logic issues, and implementing clean, maintainable fixes that improve user experience and reliability. My Approach: -> I’ll review your frontend and backend logic to identify fragile areas, inefficiencies, and inconsistencies affecting user flows. -> Fix interaction bugs, ensure actions trigger correctly, and smooth out any subtle UI glitches. -> Improve state management and data rendering so the app behaves consistently across core flows. -> Each fix will be documented and explained clearly, so you understand the improvements. I would love to begin with the code and functionality audit you described and provide a clear roadmap for improvements. Once you see the quality and clarity of my fixes, we can explore ongoing collaboration for further development and feature enhancements. Best regards, Niral
$50 USD in 40 days
8.0
8.0

Hello!! " Expert Full-Stack App Improvement & Debugging " I have similar kind of expertise and work experience. I am having more then 10+ years of experienced in programming and i believe that i can start working step by step and achieve the project goal in short time frame. Key Approach & Features: -->> Comprehensive Audit: Review frontend & backend logic, state management, and data flow for inconsistencies. -->> UI/UX Fixes: Correct interaction bugs, align workflows, and ensure seamless user experience. -->> Performance & Stability: Identify fragile areas, optimize rendering, and reduce errors. -->> Code Integrity: Implement fixes cleanly, with modular, maintainable, and well-documented code. -->> Cross-Platform Consistency: Ensure all user actions work as expected across devices and platforms. -->> Continuous Collaboration: Provide clear explanations and suggestions for ongoing improvements. I WILL PROVIDE 2 YEARS OF FREE ONGOING SUPPORT AND COMPLETE SOURCE CODE. WE WILL WORK WITH AGILE METHODOLOGY AND WILL ASSIST YOU FROM ZERO TO PUBLISHING ON STORES. I am interested in this project. Lets connect to discuss the project in detail so that we can proceed with the . Thanks Julian
$50 USD in 40 days
8.5
8.5

Hi, I’ve spent 5 years as a senior developer and team lead, working extensively with PHP frameworks like Laravel and CodeIgniter, as well as JavaScript frameworks such as Vue.js and React.js. I’ve led multiple projects from scratch, managing everything from server setup to CI/CD pipelines. I’m also a strong advocate for Agile methodologies, which I believe are essential for delivering high-quality products that truly meet user needs. In addition to web development, I’ve expanded my expertise to mobile app development using frameworks like Flutter and React Native, allowing me to offer a more versatile skill set. Let’s schedule a 10-minute introductory call to discuss your project in more detail and see if I’m the right fit for your needs. I’m eager to learn more about your exciting project. Best regards, Adil
$50 USD in 40 days
7.4
7.4

Hi, I am a senior full-stack developer experienced in auditing and stabilizing existing mobile and web applications. I specialize in quickly understanding production codebases, identifying subtle logic or UI inconsistencies, and implementing clean, targeted fixes without disrupting existing architecture. My expertise spans frontend and backend review, state management improvements, and reliability enhancements to ensure smooth, consistent user experiences. I can carefully audit your application, resolve interaction bugs, improve data rendering, and document all fixes for clarity. My approach prioritizes precision and efficiency, delivering stability improvements while preserving the system’s integrity. I have successfully optimized production apps and am ready to provide ongoing support if needed. Best, Justin
$50 USD in 40 days
6.5
6.5

Hello, I can help audit, debug, and refine your existing application to improve stability, logic flow, and overall user experience. With strong full-stack experience, I’m comfortable reviewing both frontend and backend systems, identifying hidden issues, and implementing clean fixes without disrupting the current architecture. My approach begins with a structured code and functionality audit: reviewing core user flows, state management, UI behavior, and backend logic to detect inconsistencies or fragile areas. I then implement targeted improvements—fixing interaction bugs, stabilizing data rendering, and ensuring user actions consistently trigger the correct outcomes across the platform. All fixes will be well documented with clear explanations, so your team understands the improvements and can maintain the system easily. I focus on practical solutions that strengthen reliability while keeping the application scalable for future updates. Thanks, Asif.
$50 USD in 40 days
6.5
6.5

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, 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 , java spring boot and php CodeIgniter mvc. Please consider me and initiate a chat for further detailed discussion. Regards, Anju
$50 USD in 40 days
6.6
6.6

Hello, You already have a functional application and need a developer who can carefully review the system, identify UX and logic inconsistencies, and implement clean fixes without disrupting the current architecture. I specialize in analyzing existing codebases, debugging complex frontend/backend interactions, and stabilizing production applications. My approach is to first perform a structured code and workflow audit, then address UI/UX issues, state management problems, and fragile logic areas while maintaining consistency across the platform. All fixes will be clearly documented so your team can easily maintain and extend the system. Estimated completion time: Initial audit and fixes within 5–7 days.
$50 USD in 40 days
6.1
6.1

Hi, I came across your project "Expert Full-Stack App Improvement & Debugging" and I'm confident I can help you with it. About Me: I'm a agency owner with over 8+ years of experience in PHP, JavaScript, Website Design, Mobile App Development, Full Stack Development, Mobile App Testing, Frontend Development, Web Development. , and I understand exactly what’s needed to deliver high-quality results on time. Why Choose Me? - ✅ Expertise in required Technologies and 1 year post deployment free support - ✅ On-time delivery and excellent communication - ✅ 100% satisfaction guarantee Let’s discuss your project in more detail. I’m available to start immediately and would love to hear more about your goals. Looking forward to working with you! Best regards, Deepak
$50 USD in 40 days
6.0
6.0

Hello , I am a seasoned full-stack developer with expertise in PHP, JavaScript, website design, and mobile app development. I have a strong track record of improving and debugging existing applications to enhance user experience and stability. I understand the importance of auditing codebases, fixing UI/UX inconsistencies, and ensuring seamless functionality across platforms. My approach involves meticulous review, targeted fixes, and clear documentation of improvements. With a focus on maintaining existing architecture while implementing enhancements, I am confident in my ability to identify and resolve issues efficiently. My portfolio includes successful projects where I have optimized production apps and improved user interactions. I am eager to discuss how I can assist in refining your application. Let's connect to explore further. Best regards,
$50 USD in 40 days
5.9
5.9

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