Zain I.

I'm a Senior Flutter Developer with 5+ years of experience building and fixing production mobile apps for iOS and Android. I currently work as a Senior Software Engineer at Stratagile, where I've shipped a range of production apps including delivery platforms, booking systems, a hotel management system, banking applications, and a kids' video streaming platform, alongside freelance work here on Upwork with completed jobs. What I'm best at Clients generally come to me for one of two things: building a new Flutter app from the ground up, or resolving issues in one that's already live and breaking. The second is where I've built the strongest track record production crashes, Firebase login and authentication failures, bug fixes, feature implementation on existing codebases, and backend migration issues. A few recent examples from completed projects: Diagnosed a production app crash directly from crash logs and shipped a fix without disrupting any other part of the app Resolved a Firebase login issue the same day it was reported, with a clear explanation of root cause Fixed authentication and data sync issues during a Supabase backend migration, with zero data loss Handled bug fixes and feature implementation on an existing Flutter codebase I hadn't originally built If your app is live and something just broke — a crash, a login failure, a sync issue — I can usually scope the fix within hours of seeing the logs, not days. What I build with Flutter and Dart for the app layer; Firebase and Node.js for backend and custom APIs; MySQL, SQLite, and MongoDB depending on the data needs; and Supabase when a project calls for it. For state management, I work comfortably across Provider, GetX, Riverpod, and the Bloc pattern, and I follow MVC and standard design-pattern practices to keep codebases maintainable for whoever touches them next — including you, if you bring on another developer later. Integrations I've shipped in production Firebase Cloud Services, AdMob, OneSignal, Agora (real-time audio/video calling), Google Maps, payment gateways, SMS gateways, push notifications, in-app purchases, and barcode/QR scanning. I also set up CI/CD pipelines with GitHub Actions and Codemagic so builds and releases aren't a manual headache. How I work I respond within a few hours. I'll tell you upfront whether something is a quick fix or a real build (and price/time it honestly either way), and I keep communication direct; clients have consistently noted clear communication and reliability as what they remember most. I hold a 100% Job Success Score and Top Rated status on Upwork, and I'm available 40-50 hours/week for the right project. Send me what's broken or what you want built, and I'll give you a straight answer on scope and timeline before we start.