I run a service-based company and need a custom solution that lets my team generate invoices, send them to clients, and collect payments without jumping between different platforms. The core of the project is a web application with companion mobile apps (iOS and Android) so staff in the field can create or update an invoice, apply discounts or taxes, and take a card, wallet, or bank transfer payment on the spot. The web portal should give me an at-a-glance view of outstanding balances, payment history, and basic customer data. Clients must receive branded PDF invoices by email or push notification and be able to settle them through integrated gateways such as Stripe, PayPal, and, if possible, a local bank API. Automatic reminders, recurring billing, and exportable reports (CSV/PDF) are also important. I have no fixed deadline, so the focus is on a clean architecture, strong security, and clear documentation. A RESTful API, cloud-ready deployment, and source-controlled code are expected so future features can be added easily. Deliverables • Web-based admin portal • Cross-platform mobile app (iOS & Android) • Secure backend API and database schema • Payment gateway integrations and test sandbox setup • Complete source code, basic user guide, and deployment assistance Acceptance will be based on end-to-end testing with sample data, successful processing of test payments, and smooth installation in a cloud environment of my choice.