React Web App Mobile Conversion

I would like to create a mobile app based off of our employee portal.
need push notifications and location trackign for time punches, clocking in and out for a shift.
I have a production React web application and now need a companion mobile experience that feels fully native on both iOS and Android. The goal is to reuse as much of the existing React codebase as practical—most likely by migrating the UI and business logic into React Native or a comparable cross-platform framework—while integrating device-specific capabilities.

Key features that must be present from day one:
• User authentication that mirrors the current web flow (email / social log-ins, session handling).
• Push notifications delivered via APNs and FCM, wired to the existing backend.
• In-app messaging exactly as it works on the web, adapted to a mobile-friendly layout.

Deliverables
1. Source code for the iOS and Android apps, structured for long-term maintainability.
2. Build scripts or CI configuration so I can generate new releases with a single command.
3. Test builds (.ipa and .apk) followed by production-ready submissions that meet App Store and Google Play guidelines.
4. Brief hand-off documentation covering environment setup, key architectural decisions, and how to extend or patch features.

Acceptance criteria
• All three features above are fully functional on real devices.
• Performance and navigation match modern mobile UX standards—no obvious “webview” feel.
• App review passes on both stores without needing major rework.