> For the complete documentation index, see [llms.txt](https://ftcoders.first-tech.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ftcoders.first-tech.com/first-tech-ttp-sdk/nfc-contact-and-payment.md).

# 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.

***

<figure><img src="https://732834971-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FRHBTYHK49B1fSJrGzk2y%2Fuploads%2FPMMOA0snXJlLkomRpMCW%2FSe%C3%A7%C3%A3o%204%20aproxima%C3%A7%C3%A3o%20do%20cart%C3%A3o.png?alt=media&amp;token=4bb4d28f-cd79-4e0e-bf0c-436cb63d220d" alt=""><figcaption></figcaption></figure>

## NFC Contact Screen

### 01 - Amount and payment type&#x20;

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

### 02 - Contactless illustration&#x20;

Must clearly indicate the proximity gesture between card and device

### 03 - Active NFC indicator&#x20;

Animated or pulsating icon signaling readiness to scan

### 04 - Promotional coupon (optional)&#x20;

May be shown at the bottom as a loyalty incentive

### 05 - Accepted payment methods&#x20;

Display updated icons of supported card networks and wallets

{% hint style="success" %}
**Mandatory:**&#x20;

The screen must block secondary interactions and focus user attention on the NFC action.
{% endhint %}

{% hint style="info" %}
**Recommended:**&#x20;

Provide haptic or audio feedback when a compatible card or phone is detected.
{% endhint %}

***

## Approved Transaction

### 06 - Success indicator&#x20;

Green circle with checkmark and the message “Transaction approved”

### 07 - “Send receipt” button&#x20;

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

### 08 - “Finish purchase” button&#x20;

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

{% hint style="success" %}
**Mandatory:**&#x20;

Feedback for success must appear instantly (<1s after approval).
{% endhint %}

{% hint style="info" %}
**Recommended:**&#x20;

Reiterate the amount and payment method on the confirmation screen for visual assurance.
{% endhint %}

***

## Declined Transaction

### 09 - Error indicator&#x20;

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

### 10 - “Cancel” button&#x20;

Must terminate the payment process and return to the catalog

### 11 - “Try again” button&#x20;

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

{% hint style="success" %}
**Mandatory:**&#x20;

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

{% hint style="info" %}
**Recommended:**&#x20;

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

***

## 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.


---

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