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We are looking for an experienced developer to enhance and improve an existing web and mobile application. The work includes fixing existing issues, improving UI/UX, optimizing performance, adding new features, integrating APIs, and ensuring smooth functionality across web and mobile platforms. The developer should be able to understand the existing codebase and deliver clean, scalable, and reliable improvements.
Project ID: 40634249
63 proposals
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Active 6 days ago
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Hi There!!! I understand you need an experienced developer to improve an existing web and mobile application while keeping the code clean, scalable, reliable, and easy to maintain. Support can cover existing issue fixes, UI and UX improvements, performance optimization, new feature development, API integrations, responsive behavior, and smooth functionality across web and mobile. The existing codebase can be reviewed first to ensure improvements fit the current architecture. Happy to discuss the application, current challenges, and upcoming features in a quick chat. Best Regards, "Hussain Ahmed" 1. Can you share the existing application? 2. Which issues should be fixed first? 3. Are the required APIs already available?
₹5,500 INR in 13 days
0.0
0.0
63 freelancers are bidding on average ₹8,487 INR for this job

With a solid background in full-stack development and a keen eye for enhancing user experiences, I am well-equipped to tackle the challenges posed by your web and mobile application project. I have successfully optimized performance and integrated APIs in previous projects, ensuring seamless functionality. How important is maintaining backwards compatibility with the existing codebase for this project? Regards, Yogesh Kumar
₹4,790 INR in 9 days
7.8
7.8

As an AI-focused software development team, we have a keen eye for enhancing existing systems. We understand not only how to fix issues and introduce new features but also the importance of optimizing performance and improving UI/UX for better engagement. With solid experience in web and mobile app development using JavaScript, Node.js, React Native, and Mobile App Development, our team is well-equipped to understand your codebase and deliver clean, scalable, and reliable improvements. What differentiates us is our dedication to automation. We have successfully built resilient AI-powered systems and intelligent workflows that have drastically reduced manual workloads, improved customer journeys, and enhanced overall business operations. Our specialties in an AI-powered CRM system, business workflow automation, AI-lead qualification systems make us the perfect fit for this project. We are excited about the opportunity to contribute to your web and mobile app enhancement journey. Putting our expertise in MCP server development, API integrations and Cloud Infrastructure & DevOps at work along with a knack for detail orientation will ensure smooth functionality across web and mobile platforms fostering an impeccable user experience.
₹7,000 INR in 1 day
7.1
7.1

Hi, Your project is exactly the kind of work I enjoy—improving an existing product instead of rebuilding it. I can quickly understand your current web and mobile codebase, fix bugs, optimize performance, refine the UI/UX, integrate new APIs, and implement new features while keeping the code clean and scalable. I've worked extensively with React, Flutter, React Native, Node.js, and Laravel on production applications. Could you share the current tech stack and a list of the highest-priority issues so I can propose the best approach? Best, Mehboob
₹9,000 INR in 7 days
6.0
6.0

Hello, I reviewed your project requirements for Web & Mobile App Enhancement and Feature Development . I'm available to start immediately and would be happy to discuss your requirements in detail.
₹12,500 INR in 3 days
5.9
5.9

Hi, I can fix the existing issues, improve the UI/UX, and add new features across your web and mobile app without breaking what already works. I'll review the current codebase first, then handle fixes and API integrations in small, tested updates. You will receive: Bug fixes and performance improvements UI/UX updates across web and mobile API integrations and new features working I understand smooth cross-platform functionality is the priority. I can start within a day of getting access. 1) What tech stack is the current app built on? Best regards, Shayan
₹1,650 INR in 4 days
5.3
5.3

Hi, As someone who has been deeply immersed in the world of software development for over 7 years, I believe I am the perfect fit for your project. My developer skill set and expertise spans various areas such as JavaScript, Node.js, API integration and that proficiency will come very handy when mending your broken functionalities and implementing new features to your application. My aim is to deliver clean, scalable and reliable improvements; ensuring smooth functionality across web and mobile platforms. Being well versed with different frameworks, databases and platforms such as React, Angular, Python among others gives me an added advantage in this pursuit. Let's join forces with the goal of breathing more life into your app!
₹7,000 INR in 7 days
5.5
5.5

Hi there, Fixing, optimizing, and extending an existing web + mobile app across platforms — I'll start by getting familiar with your current codebase before touching anything, so changes stay consistent with what's already there. What I'll do: ✅ Audit the codebase, flag existing bugs and quick wins first ✅ Fix issues, then move to UI/UX and performance improvements ✅ Add new features and API integrations cleanly, without breaking existing functionality ✅ Test across web and mobile to confirm smooth cross-platform behavior ✅ Full-stack web + mobile development ✅ API integration, performance optimization, UI/UX improvements Why me: I have worked here with more than 130+ clients. One quick question: what's the current stack (framework/language) for web and mobile? Available now — let me know your budget/timeline and I'll confirm.
₹9,500 INR in 2 days
5.2
5.2

With over 8 years of valuable experience under my belt, I am well-equipped with the skills and expertise necessary to enhance and improve your existing web and mobile application. From fixing existing issues to adding new features, I have a firm grasp on optimizing UI/UX, performance, and continuous functionality. My proficiency in Flutter, JavaScript, Mobile App Development, and Web Development is exactly what is needed to truly make a difference for your app. One aspect that sets me apart from other developers is my innate ability to understand complex codebases quickly, while still delivering clean and scalable improvements. With a keen eye for detail and knack for troubleshooting, I provide not just short-term solutions but also long-term technical support to safegaurd your digital investment. Finally, a key advantage of choosing me is the value I place on not just meeting deadlines but also effective communication throughout the project. On-time delivery combined with fast communication ensures we stay on the same page at all times. Let's leverage my industry experience to transform your application into an even more exceptional one together. I am excited to learn more about your project and deliver solutions that drive growth and efficiency while greatly enhancing user experience.
₹17,500 INR in 7 days
5.5
5.5

Hi, I can help enhance your existing web and mobile application by first auditing the current codebase, identifying bottlenecks and technical issues, and then delivering improvements without disrupting existing functionality. I have experience with UI/UX refinement, performance optimization, API integrations, bug fixing, responsive web/mobile development, and scalable backend workflows. I’ll focus on clean, maintainable code, reliable functionality, and consistent user experience across devices. I recommend working in milestones: codebase audit, priority bug fixes, UI/UX improvements, performance optimization, API/new feature integration, then full QA and deployment. I’ll provide regular progress updates and clear documentation. I can start immediately and work efficiently toward a stable, polished release. Best regards, Jagrati
₹15,000 INR in 7 days
4.9
4.9

You need a developer who can take over an existing web and mobile app, fix issues, improve UX, optimize performance, and add new features without breaking the current codebase. I have 9+ years of full-stack experience building and improving production applications with React Native, Node.js, JavaScript, and modern web stacks. I focus on understanding existing architecture first, then making targeted improvements, API integrations, and performance fixes. At Poundit (Philippines), I worked on an e-commerce platform using Django, Node.js, and Vue/Next frontend, including payment flows and automation features. I have also delivered cross-platform mobile apps with React Native and Flutter. For your project, I can review the current app structure, identify bottlenecks, fix bugs, improve UI/UX, and add required features with clean code practices.
₹10,000 INR in 3 days
4.5
4.5

One important aspect of being a technologist today is having the ability to analyze and understand existing code bases— something core to my expertise. Its only when you truly comprehend what you're working with can you craft reliable improvements. Furthermore, my libraries of skillsets extend across various industries like e-commerce, education and healthcare to name a few; I am equipped to design something truly unique for you. I firmly believe in transparent project management and clear communication – these values will guide us throughout our work together. More than just providing quality coding and development, I am dedicated to building long-term relationships based on trust. My aim is not only delivering a robust application but also creating solutions that improve efficiency, increase revenue, and scale with the business. Let's connect! Let me bring your vision to life with a structured roadmap for its implementation.
₹7,000 INR in 5 days
4.8
4.8

Hi, Thanks for sharing your project. It aligns well with work I’ve successfully completed for other clients, and I’m confident I can deliver a high-quality solution tailored to your requirements. Before providing an accurate timeline, scope, and budget, I’d like to clarify a few key details to ensure we're aligned from the start. Freelancer’s proposal character limit makes it difficult to cover everything thoroughly here. If you're available, let's connect via chat. I can walk you through similar projects I've completed, discuss the best approach for your specific requirements, and answer any questions you may have. Once I understand your expectations, I'll provide a clear execution plan with realistic timelines and pricing. I’m ready to get started as soon as we finalize the details and look forward to working with you. Best regards, Mayank Sahu
₹7,000 INR in 7 days
4.0
4.0

Dear client, I have reviewed your project requirements and would like to offer you Web & Mobile App Enhancement and Feature Development at a reasonable price. I will provide you website with very good quality work and ensure that you are completely satisfied with the final outcome.
₹12,500 INR in 3 days
4.0
4.0

Hello, Enhancing the web and mobile application involves more than just fixing issues and adding features. It's about creating a seamless user experience that functions flawlessly across platforms. I would start by reviewing the existing codebase to understand the current architecture and identify areas for improvement. Prioritizing UI/UX enhancements and performance optimization will be crucial to ensure a user-friendly and fast application. Integrating APIs seamlessly and maintaining clean, scalable code will be my focus to deliver reliable improvements. I have experience in similar projects where the goal was to enhance existing applications while maintaining functionality and improving user experience. A few questions: - Are there any specific APIs that need to be integrated? - What are the key performance metrics to optimize? - Which existing features require immediate attention? Best regards,
₹7,000 INR in 2 days
3.6
3.6

Hi there! Working across an existing codebase without breaking what's already running is exactly the kind of job I enjoy — fixing bugs, tightening UI/UX, and layering in new features without introducing regressions. I'll start by auditing the current web and mobile app to map out weak points in performance and UX, then move into fixes, API integrations, and feature additions with clean, scalable code that fits your existing architecture. Structured for traceability throughout, so you always know what changed and why. I recently built a hyperlocal marketplace app (Mohollla) live on both Android and iOS with real-time multi-role sync — same care applies here. Let's align on which areas (web, mobile, or both) need priority first — once scope is clear, I'll make sure it works within your budget comfortably. Quality execution is always my priority. Looking Forward to work together. Regards Sakshi.
₹9,500 INR in 7 days
3.6
3.6

Hi, We can help improve your existing web and mobile application without disrupting the current system. We can handle: Existing bug fixes and issue resolution UI/UX improvements and responsive design Performance optimization New feature development REST API integration and enhancements Web & mobile functionality improvements Code cleanup and scalable architecture Testing and cross-platform QA Deployment and post-development support We’ll first review the existing codebase, identify priority issues, and create a clear improvement plan before making changes. This ensures the updates remain stable, maintainable, and scalable rather than requiring unnecessary rewrites. I’m comfortable working with existing applications and can start with a codebase audit.
₹7,000 INR in 7 days
4.4
4.4

**Proposal – Web & Mobile Application Enhancement** Hello, Greetings from **Elixir Infotech**! We would be happy to help improve and enhance your existing web and mobile application. Our experienced development team can quickly understand your existing codebase, identify issues, and implement reliable improvements without disrupting current functionality. ### We Can Help With: • Existing bug fixing and issue resolution • UI/UX improvements and responsive design • Performance optimization and faster load times • New feature development • REST API and third-party API integration • Database/backend improvements • Web & mobile compatibility • Security, stability and error handling • Code cleanup and scalable architecture • Testing and production deployment We have strong expertise in **Flutter, Android, web applications, Firebase, REST APIs, backend integration, and third-party services**. We follow a structured approach: first review the existing codebase, identify priorities, then implement and test improvements in milestones. We focus on **clean, maintainable code, smooth user experience, performance, and long-term scalability**. Please share the existing application/codebase, current issues, and required enhancements. We can review the project and provide a **clear development plan, timeline, and cost estimate**. Looking forward to working with you. **Regards,** **Elixir Infotech** Rajkot, Gujarat, India Flutter | Android | Web | Firebase | API Integration
₹7,000 INR in 7 days
3.6
3.6

Hi, Improving an existing product is often more valuable than rebuilding it, because the goal is to preserve what already works while making the experience faster, cleaner, and more reliable. I have experience enhancing web and mobile applications, fixing bugs, refining UI/UX, integrating APIs, and adding scalable features within existing codebases. I can quickly understand your architecture, prioritize the highest-impact improvements, and deliver clean, production-ready updates across both platforms. I’d be glad to review the current app and discuss the next development priorities. Thanks, Srdan.
₹8,500 INR in 3 days
3.4
3.4

Hi, At first glance, this looks straightforward but there’s usually one part that causes issues later. I’ve handled similar work before and can help you avoid that. Regards, Rajesh
₹7,000 INR in 7 days
3.1
3.1

I will begin by auditing the existing application codebase to fully understand the current state of the web and mobile application. The first execution step involves prioritizing the fixing of existing issues and optimizing performance across both platforms. I will then focus on implementing the requested new feature development, ensuring seamless integration with the existing APIs. The subsequent phase involves enhancing the UI/UX to improve the overall user experience for all users. Deliverables will include a refactored codebase, updated UI components, and fully functional new features, which will be checked via platform testing and a final functional review. To ensure smooth execution, can you provide access to the current API documentation for the integration work?
₹7,000 INR in 7 days
2.9
2.9

Bhopal, India
Member since Nov 3, 2020
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