Multi-Carrier Prepaid Recharge System

I want to build a streamlined prepaid phone-recharge service that lets customers top-up numbers from several carriers in one place. The core requirement is support for multiple networks right out of the gate rather than locking the flow to a single operator.

You are free to recommend whether the experience should launch first as a mobile app, a web portal, or both; the key is to keep the checkout fast, intuitive and secure. Real-time balance updates, automated PIN delivery (where applicable) and reliable payment-gateway integration (Stripe, PayPal or a solid local alternative) all matter to me.

Please factor in:
• Carrier catalogue management with denomination, promo and validity controls
• Transaction logging plus simple admin dashboard for refunds or manual adjustments
• Clean API endpoints so future partners or resellers can plug in without rewriting code

Deliverables I expect:
1. Working recharge front end and admin panel, fully branded.
2. Tested integrations for at least three distinct carriers.
3. Deployment guide with environment variables, build commands and rollback steps.

If you have shipped recharge or bill-pay products before, show me a demo or short screencast so I can feel the flow. Looking forward to your approach and timeline.