Device agnostic single verification digital payment processing system for accepting payment from a user device at a brick and mortar point of sale terminal

An electronic payment system based on using electronic coupons for executing transactions between a user device and a point-of-sale terminal at a brick-and-mortar retail location, the electronic payment system comprising:

• a vendor system, as implemented by a processor on a computer, the vendor system selectively connectable via a network to one or more external vendor point-of-sale (POS) systems at brick-and-mortar retail locations, each external vendor POS system associated with a vendor offering at least one item or service for purchase by customers, the vendor POS system including a vendor POS coupon database storing coupon data defining one or more coupons issued by that vendor, each coupon defining at least one of an item and a service available from the vendor for purchase;
• and
• a payment integration system for interfacing via a network connection with an external payment processing system that electronically and separately processes payments being executed by users using user devices to make purchases from vendors, the payment integration system selectively providing a gateway on the network connection to a banking system that enables a user with a user device to complete an electronic payment via the user device, to purchase an item and/or service from a vendor,
• wherein the vendor providing the item and/or service being purchased by the user uses the coupon data stored in the vendor POS coupon database as a means to verify that a payment for the item and/or service being purchased has been successfully completed.

A method, as implemented by a processor on a computer selectively connectable to a network, using machine-readable instructions stored in a non-transitory memory device accessible by the processor, the method comprising:

• receiving information from a user device as related to a purchase transaction desired by a user;
• identifying brick-and-mortar retail vendors relevant to the desired purchase transaction and present the relevant venders to the user device;
• based on the purchase transaction selections obtained from the user device, identifying appropriate product and/or service options available for selection by the user;
• receiving an indication of which vendor and which product and/or service the user selects;
• providing a payment gateway for the user to execute a payment using the user device for the selected product and/or service;
• receiving a confirmation of receipt of payment from one of the user's user device and the payment gateway;
• based on the user selections, obtaining data for a coupon issued by a vendor providing the selected product and/or service and indicated as having a status of “unused”;
• transforming the coupon data to generate a coupon in a display format for presentation to the vendor;
• and
• transmitting the coupon to the user device for presentation by the user to the vendor, so that the user can claim the selected product and/or service from the vendor.