I’m building a single app for both iOS and Android that lets anyone buy a virtual phone number at a fixed, up-front price and immediately use it to create or verify WhatsApp, Telegram, Facebook, and other social-media accounts. Core flow • Users create an account with a simple e-mail-and-password sign-up. • They enter the exact phone number they want; the app checks my supplier’s pool in real time and confirms availability. • Once paid for, the number is locked to that customer and incoming SMS codes are displayed inside the app so they can finish the third-party registration. Key requirements • Native-quality cross-platform build (Flutter, React Native, or similar) for iOS + Android. • Secure payment gateway integration for the fixed price purchase. • API integration with the virtual-number provider (I can supply documentation or you can recommend one). • In-app inbox for SMS verifications, with push notifications. • Lightweight admin panel to upload or sync new number blocks, set prices, and monitor sales/usage. Acceptance criteria 1. A fresh user can register, search for a number, pay, and receive at least one live SMS code from WhatsApp in a single session. 2. Purchased numbers are removed from the public pool and visible only in the buyer’s account. 3. Clean, responsive UI passes App Store & Play Store review guidelines. Code, documentation, and deployment support to TestFlight and a closed Play Store track complete the deliverable.