NFC Contact and Payment

Objective

Establish the minimum requirements for the interface and system behavior during the NFC payment phase, when the card or device is tapped. This step is critical to the user experience and requires clarity, real-time feedback, and perceived security.

Insights

• NFC animations must follow platform standards (Android/iOS) for security and compatibility.

• The proximity illustration must respect proportionality and semantics between hand, card, and phone.

• This screen must be tested in different contexts: embedded POS, mobile NFC devices, digital wallets.

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NFC Contact Screen

01 - Amount and payment type

Must be clearly displayed (e.g., “R$ 122.00 – Credit one-time”)

02 - Contactless illustration

Must clearly indicate the proximity gesture between card and device

03 - Active NFC indicator

Animated or pulsating icon signaling readiness to scan

04 - Promotional coupon (optional)

May be shown at the bottom as a loyalty incentive

05 - Accepted payment methods

Display updated icons of supported card networks and wallets

Mandatory:

The screen must block secondary interactions and focus user attention on the NFC action.

Recommended:

Provide haptic or audio feedback when a compatible card or phone is detected.

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Approved Transaction

06 - Success indicator

Green circle with checkmark and the message “Transaction approved”

07 - “Send receipt” button

Must allow sending the receipt via email, WhatsApp, or other configured channels

08 - “Finish purchase” button

Must complete the operation and return to the home screen or an empty cart state

Mandatory:

Feedback for success must appear instantly (<1s after approval).

Recommended:

Reiterate the amount and payment method on the confirmation screen for visual assurance.

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Declined Transaction

09 - Error indicator

Red circle with an “X” and the message “Transaction declined”

10 - “Cancel” button

Must terminate the payment process and return to the catalog

11 - “Try again” button

Must restart the NFC scanning process while keeping the current transaction data intact

Mandatory:

Messages must be clear and not blame the user (“Card declined”, not “User error”)

Recommended:

If possible, show the reason for failure (e.g., “Insufficient funds”, “Expired card”).

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Mandatory Messages

• On successful payment:

  Transaction approved. Thank you!

• On failed payment:

  Transaction declined. Please check your card or try another payment method.

Expected Behaviors

• The NFC screen must remain active for up to 60 seconds or until manually cancelled.

• NFC response must occur in real time (max. 2 seconds latency).

• Users must have clear control to retry or exit the flow.

• After an error, the NFC module must be fully reset before a new attempt.