Accountant Client-Request App Development

I need a polished mobile application that lets a professional accountant stay on top of every client interaction from one place. The app must launch on both iOS and Android, ideally from a single code-base (React Native, Flutter or a comparable cross-platform framework) to keep future maintenance straightforward.

Core feature set
• Client Management – add, view, edit and archive client profiles with basic contact and engagement details.
• Request Tracking – each client can raise service requests that flow through open, in-progress and completed states, stamped with dates and notes.
• Financial Reporting – simple visual dashboards and downloadable PDFs summarising balances, invoices and year-to-date performance.
• Communication Hub – in-app chat plus the ability to send/receive emails and message threads, all stored against the relevant client record.
• Push Notifications – the accountant receives an instant alert whenever a new request or message arrives.

Key expectations
• Clean, intuitive UI that feels at home on both platforms.
• Secure sign-in (OAuth or similar) and encrypted data storage.
• Well-structured, documented code plus clear instructions for building the iOS and Android releases.
• Handoff of design assets, source code and a brief video walkthrough so I can demo the finished product to stakeholders.

If you have shipped cross-platform apps with real-time messaging or finance modules before, I would love to see your work.