I have an existing Flutter mobile app (Firebase backend + RevenueCat + web scraping). Most functionality is already implemented. I need an experienced Flutter developer to update and refine several features. I believe this should not take more than a few days for an experienced developer. Scope of Work: 1. Sync Local Storage with Firestore (Offline Support) - Keep using local storage for offline mode - Sync shift data with Firebase Firestore - Handle offline → online auto sync - Prevent duplicates (unique shift ID) - Secure Firestore rules (user-only access) - Ensure cross-device sync works properly 2. Fix Email Verification (Spam Issue) - Configure Firebase Auth to use custom domain (syncmyschedule.com) - Set up SPF, DKIM, DMARC - Improve email template - Ensure emails land in inbox (Gmail/Outlook) 3. RevenueCat Subscription Fix - Verify subscription logic - Fix free trial fetch limits - Update UI status (trial / monthly / annual / expired) - Test restore purchase 4. UX Improvements - Simplify onboarding - Improve navigation clarity - Make main actions more intuitive 5. Minor Improvements - Improve scraping speed (if possible) - Update external calendar display format Requirements: - Strong experience with Flutter - Firebase (Auth + Firestore) - RevenueCat integration - Offline-first data handling - Clean, maintainable code This is a simple, already-built app — not a full rebuild. Please include: - Similar projects you've worked on - Estimated timeline