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I will fix any react native bug or build your hybrid mobile app ios app android app
Umer D
4.8
4.8
About this gig
Stop losing users to app crashes and lag. Hire a Senior React Native Expert to rescue your project!
Is your mobile application struggling with slow transitions, memory leaks, or random crashes? As a Senior React Native Developer with 5+ years of experience and a BSc in Computer Science, I specialize in identifying and fixing high-priority performance bottlenecks and complex technical debt.
I dont just apply "band-aid" fixes. I use advanced profiling tools to find the root cause of issues in both the JavaScript layer and the Native modules.
️ Specialist Debugging Services:
- Performance Optimization: Fixing 100% CPU usage, slow FlatLists, and frame drops (achieving 60FPS).
- Memory Management: Identifying and resolving memory leaks using Flipper and Xcode Instruments.
- Complex Bug Fixing: Squashing race conditions, Redux state desyncs, and navigation glitches.
- Native Bridge Issues: Debugging custom Native Modules (Java/Kotlin & Swift/Objective-C).
- Version Upgrades: Smoothly migrating legacy apps to the latest React Native versions (0.70+).
- Store Rejections: Fixing technical policy violations to get your app approved fast.
My Professional Workflow:
- Deep Audit: Analyzing your codebase and
Get to know Umer D
Umer D
Expert full stack website and mobile developer for scalable mobile solutions
- FromPakistan
- Member sinceNov 2020
- Last delivery2 years
Languages
Urdu, English
I’m a Senior Full-Stack Developer with 5+ years of experience in React.js and React Native. I build scalable, high-performance web and mobile applications with clean, maintainable code. My expertise includes Node.js, MongoDB, Firebase, Supabase, Redux Toolkit, REST APIs, and iOS/Android deployment. I specialize in E-commerce, FinTech, SaaS, and custom business solutions. Let’s turn your idea into a reliable, production-ready product.
FAQ
Can you fix crashes that only happen in Production but not in Development?
yes. Production-only crashes are often related to minification, ProGuard rules, or race conditions in the native bridge. I use tools like Sentry, Firebase Crashlytics, and New Relic to trace the stack logs and identify the exact line of code causing the failure in your live app
How do you identify a memory leak in a React Native app?
I use professional profiling tools like Flipper, Xcode Instruments (Leaks/Allocations), and Android Studio Profiler. I monitor the heap growth over time to identify unmounted components or listeners that aren't being cleaned up, ensuring your app's RAM usage remains stable.
My app is slow and "stuttering." Can you achieve a 60 FPS frame rate?
Absolutely. Most "stuttering" is caused by heavy JS-thread activity or unnecessary re-renders. I optimize this by implementing Memoization, flattening the component tree, optimizing FlatList props, and offloading heavy tasks to the native thread using Reanimated 3 or Worklets.
Can you fix build errors in Xcode (iOS) or Gradle (Android)?
Yes. Build failures are common after upgrading React Native versions or adding new packages. I am an expert in resolving CocoaPods conflicts, Header Search Path issues in Xcode, and Gradle dependency mismatches in Android Studio.
Do you provide a technical report of the fixes made?
Yes. As a senior developer, I provide a clear summary of every bug identified and the solution implemented. I also include best-practice recommendations to help your team prevent the same performance issues from recurring.
Can you help if my app was rejected by the App Store/Play Store?
Yes. I can fix technical rejections related to IPv6 compatibility, metadata, or performance issues. I will provide a build that meets the latest Apple and Google guidelines to ensure a successful resubmission.
Reviews
5 reviews for this Gig
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| (1) | ||
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Rating Breakdown
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- Recommend to a friend
- Service as described
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Most relevant
I iamblackmade
United States
Ongoing collaborationIt was ok
$50
Price
Helpful?I iamblackmade
United States
Ongoing collaborationNice guy reasonable rates
$50
Price
Helpful?J jaecrossley
United Arab Emirates
Experience working with princeumer516 has been a great one, will be looking forward to work again
$50
Price
P 
Seller's Response
Helpful?E ellishernandez
United States
The best in retouching and infographic design. Fully encompasses all details and highly responsive
$50
Price
P Seller's Response
Helpful?M mikaeladuckswor
United Kingdom
Fantastic to work with. Listens and communicates effectively and efficiently. Very responsive. I would definitely use again. Fantastic work, I am very happy with the project
$50
Price
Helpful?
Reviews
5 reviews for this Gig
| (4) | ||
| (1) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Recommend to a friend
- Service as described
Sort By
Most relevant
I iamblackmade
United States
Ongoing collaborationIt was ok
$50
Price
Helpful?I iamblackmade
United States
Ongoing collaborationNice guy reasonable rates
$50
Price
Helpful?J jaecrossley
United Arab Emirates
Experience working with princeumer516 has been a great one, will be looking forward to work again
$50
Price
P Seller's Response
Helpful?E ellishernandez
United States
The best in retouching and infographic design. Fully encompasses all details and highly responsive
$50
Price
P Seller's Response
Helpful?M mikaeladuckswor
United Kingdom
Fantastic to work with. Listens and communicates effectively and efficiently. Very responsive. I would definitely use again. Fantastic work, I am very happy with the project
$50
Price
Helpful?
