NumoPay

Numo is an Android Point-of-Sale application that enables merchants to receive Cashu ecash payments via tap-2-pay. Overview

The application acts as a simple point-of-sale terminal for receiving Bitcoin payments. When a customer approaches their phone with a supporting wallet, the app receives the ecash payment. How It Works

Using Numo is straightforward:

The merchant enters the desired amount in satoshis using the application's keypad. When they press "Charge", a payment screen appears and a type-4 forum tag is emulated with a cashu PaymentRequest string as its content. When the payer approaches their phone, their Cashu wallet will interact with the emulated tag using the NDEF protocol, reading the contents and decoding the payment request. Immediately after, the paying wallet will write a cashu token with the requested amount to the emulated tag and Numo will process it. Details of the payer-side spec are available here. Numo also supports direct lightning payments

When the merchant switches to the "lightning" tab in the payment screen, a fresh BOLT11 invoice is generated and displayed as a QR code. The contents of the emulated tag are also overwritten with "lightning:", so compatible wallets are be able to scan the BOLT11 invoice from the tag. Features

Tap-2-pay with cashu ecash and NDEF protocol Payment through Nostr Lightning bolt11 invoices Withdraw to self-custody / withdraw to lightning address. Automatic withdrawal after threshold is reached Merchant item catalogs, with pre-selectable items Merchant item baskets, which can be persisted and updated at different times Payment history and direct "Open With" integration for Cashu wallets