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You will get bug fixing and performance optimization for your Flutter app

Serhii L.Status: Offline
Serhii L. Serhii L.
5.0
Top Rated
Preview image

Let a pro handle the details

Buy Mobile App Bug Fixes services from Serhii, priced and ready to go.
Serhii L.Status: Offline
Serhii L. Serhii L.
5.0
Top Rated
Preview image

Let a pro handle the details

Buy Mobile App Bug Fixes services from Serhii, priced and ready to go.

Project details

You will get expert-level bug fixing and performance optimization for your existing Flutter app. Whether your app crashes, freezes, or just feels slow - I will analyze the problem and apply the right fix.

With 7+ years of experience in mobile and full stack development, I know how to debug, refactor, and boost Flutter apps across both iOS and Android.

This project is ideal if your app needs quick help or a deeper optimization before launch or update.
Platform
iOS
App Type
Hybrid App
Development Technology
Flutter
App Purpose
Delivery, Finance, Entertainment, Education, Health & Fitness, Lifestyle, Productivity, Shopping, Social Networking, Travel
Expertise
Cross Browser & Device Compatibility, Performance Optimization, Security
What's included
Service Tiers Starter
$150
Standard
$450
Advanced
$900
Delivery Time 2 days 5 days 10 days
Number of Revisions
123
Bug Investigation
Fix Documentation
-

Frequently asked questions

5.0
6 reviews
100% Complete
(6)
1% Complete
(0)
1% Complete
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1% Complete
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1% Complete
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Ross G.
5.00
Mar 9, 2026
Freelance Development Agreement Serhii (and his team) are very professional. They agree requirements upfront, and deliver good quality work that has been QA'ed. They integrate with your team/project seamlessly, and adapt to the tools you're already using. I'd highly recommend.

YK

Yuliia K.
5.00
Mar 2, 2026
Advanced AI Sales & Support Bot (Multi‑Channel, Database, Automation) I had a great experience working with Serhii. He did an excellent job developing our AI assistant from start to finish. Serhii carefully analyzed the requirements, solid technical solutions, and delivered everything on time.

I especially appreciate his strong expertise in AI development, structured approach to problem-solving, and clear communication throughout the entire project. Any revisions or adjustments were handled quickly and professionally.

The final result fully met our expectations — the assistant works smoothly, the logic is well-designed, and all integrations were implemented correctly.

I highly recommend Serhii and would definitely work with him again in the future.

DM

Dmytro M.
5.00
Feb 26, 2026
Embedded Systems Engineer – IoT Firmware Bug Fix & Small Feature Task (C++ , ESP32) It was a pleasure to work with Serhii. He is definitely an expert-level embedded systems engineer: responded quickly, thoroughly analyzed our request and perfectly fixed bugs with our IoT firmware. Highly recommended!

MI

Mariia I.
5.00
Feb 17, 2026
Full-Stack Developer ( Node.js / React + IoT experience ) - SaaS App Bug Fix & System Review Serhii is an experienced full-stack developer skilled in Node.js and React. He quickly helped fix a bug in my IoT app.

JS

John S.
5.00
Feb 11, 2026
Flutter Developer & React Native Developer - Mobile App Architecture Analysis & Tech Stack Decision Serhii is an excellent Flutter and React Native developer. He completed the task very quickly, provided clear and well-reasoned data, and clearly explained his solution to me. He can not only build apps but also provide strong ideas and well-reasoned arguments.
Serhii L.Status: Offline

About Serhii

Serhii L.Status: Offline
Senior Flutter Dev | Mobile Apps, AI & Full-Stack Development
100% Job Success
5.0  (6 reviews)
Kyiv, Ukraine - 8:08 am local time
Top Rated Mobile & Full-Stack Developer with 10+ years of experience, 100% Job Success, and 20+ mobile apps delivered for iOS and Android.

I help startups, founders, and product teams build production-ready mobile apps, full-stack platforms, and AI-powered products using Flutter, React Native, Kotlin, React, Python, Node.js, and modern AI APIs.

My main focus is mobile development. I build fast, scalable, user-friendly apps for iOS and Android, from MVPs to complex production systems. I can also handle the backend, web dashboard, API integrations, and AI features needed to make the product complete.

⭐️I can help you with⭐️
- Flutter app development for iOS and Android
- React Native mobile app development
- Kotlin Android development
- Mobile MVP development from scratch
- Figma to mobile app implementation
- React web apps and admin dashboards
- Backend APIs with Python and Node.js
- REST / GraphQL API integrations
- AI assistants, chatbots, and AI-powered app features, AI-agents
- OpenAI / ChatGPT, Claude, Gemini API integration
- Push notifications, maps, payments, chat, and real-time features
- Bug fixing, refactoring, performance optimization, and app release support

⭐️Key experience⭐️
- 10+ years in software development
- 20+ mobile apps delivered
- 10+ Flutter apps built from scratch
- 5+ React Native apps delivered
- 10+ AI-powered applications built
- 100,000+ installs on Google Play for one delivered product
- MVP delivery experience in 2-5 weeks

⭐️Core tech stack⭐️
- Mobile: Flutter, Dart, React Native, Kotlin, Swift
- Frontend: React, Next.js, JavaScript, TypeScript, Tailwind
- Backend: Python, Node.js, Express, Firebase, PostgreSQL, MongoDB, MySQL
- AI: OpenAI API, ChatGPT API, Google AI, Azure AI, Claude, AI assistants, AI-Agents
- Tools: Git, Docker, AWS, DigitalOcean, Figma, Jira, Trello

I have worked on products in fintech, e-commerce, health tech, education, logistics, productivity, content creation, and AI-powered applications.

Clients usually hire me when they need someone who can take ownership of the mobile app, understand the business goal, communicate clearly, and also support the backend or AI side when needed.

If you need a reliable developer to build a mobile app, improve an existing product, or add AI features to your platform, I would be happy to discuss your project.

Steps for completing your project

After purchasing the project, send requirements so Serhii can start the project.

Delivery time starts when Serhii receives requirements from you.

Serhii works on your project following the steps below.

Revisions may occur after the delivery date.

I review code and reproduce bugs

Create a prioritized fix plan

Review the work, release payment, and leave feedback to Serhii.