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I will fix mobile app flutter bugs, crashes, API errors in android, ios, react native
Helping startups and businesses build, fix, and optimize mobile and web apps
Hi, I'm Steffen Wannemaker, a professional mobile app developer and full-stack web developer. I specialize in Flutter mobile apps and modern web applications. I help startups and businesses fix bugs, ...
About this Gig
Is your mobile app crashing, showing errors, or not working properly?
Struggling with API issues, login problems, or data not loading? I'm here to help.
I specialize in Flutter mobile app bug fixing, app debugging, and fixing API errors for Android, iOS, iPhone, iPad, React Native, and Flutter apps, so your application runs smoothly, securely, and without issues.
What I Fix:
- App crashes on launch or during use
- API not connecting or returning errors
- Login/signup not working
- Firebase or database issues
- Performance issues (slow, lagging apps)
- UI bugs
What I Offer:
- Fix mobile app bugs and errors
- Debug and resolve app crashes
- Fix API integration and backend issues
- Solve login/signup and authentication problems
- Fix Firebase and database errors
- Improve app performance and stability
- Code review, cleanup, and optimization
My Process
- Analyze your app to find the root cause
- Fix bugs
- Optimize performance
- Test to ensure stability
- Deliver a working solution
Technologies:
- Flutter, React Native, Android (Java/Kotlin)
- Firebase, REST APIs, Node.js backend
- Third-party API integrations
Every bug is different. Contact me before ordering so I can review your issue and provide the best solutions.
Platform:
Cross-platforms
App type:
Hybrid
Frameworks:
Flutter
•
Laravel
•
SwiftUI
•
Node.js
Tools:
Expo
•
Android Studio
•
Xcode
My Portfolio
FAQ
Do you need access to my full source code?
Yes. I need access to your source code (GitHub, ZIP file, or repository) to properly analyze and fix the issue.
Can you guarantee the bug will be permanently fixed?
Yes. I focus on identifying and fixing the root cause, not temporary patches, so the issue does not reoccur.
What if I don’t know the exact problem in my app?
No problem. I will analyze your app and error logs to identify the issue and explain the solution before fixing it.
Do you fix both frontend and backend issues?
Yes. I fix UI bugs, app crashes, API issues, Firebase errors, and backend-related problems.
Will my app data or code be safe?
Yes. Your code and data are completely confidential and will never be shared or reused.
How long does it take to fix a bug?
It depends on the complexity. Small bugs can take a few hours, while complex issues may take 1–3 days.
Can you fix apps that are already published on Play Store or App Store?
Yes. I can debug and fix issues in both unpublished and live applications.
