Description and Purpose of the Document

This document aims to establish minimum standards for the user experience (UX) in sales applications that implement the Tap to Pay (TTP) payment method. It provides guidance on the design, implementation, and validation of interfaces, flows, and behaviors within applications used by sellers (receiving users) and customers (paying users), with a focus on efficiency, clarity, accessibility, and regulatory compliance.

The proposed standardization seeks to:

• Promote a consistent and intuitive experience across different points of sale (POS) that use TTP;

• Reduce operational errors and incomplete transactions caused by interface issues or interaction ambiguities;

• Improve user trust by reinforcing perceptions of security, speed, and convenience;

• Comply with regulatory requirements associated with proximity payment methods (e.g., PCI MPoC);

• Facilitate interoperability between systems and alignment across product, engineering, support, and compliance teams.

This document is intended for design, product, engineering, QA, and compliance teams, and must be used as a mandatory reference for the development and validation of any application integrating the TTP payment flow—whether on mobile devices, Android POS terminals, or web-based sales applications.

The visual examples and illustrative flows contained in this document are for guidance purposes only and do not impose specific visual standards, as long as the described guidelines are faithfully followed regarding user experience, clarity, and expected behavior.