> For the complete documentation index, see [llms.txt](https://docs.payments.thalescloud.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.payments.thalescloud.io/nfc-wallet-sdk-ios/implement-nfc-wallet/make-payments/implement-contactless-payment/2.-manage-the-default-payment-application.md).

# 2. Manage the default payment application

The default payment application is launched when the end user performs a [double-click](/nfc-wallet-sdk-ios/implement-nfc-wallet/make-payments/implement-contactless-payment.md#double-click) or [field-detect](/nfc-wallet-sdk-ios/implement-nfc-wallet/make-payments/implement-contactless-payment.md#field-detect) action.

The double-click payment experience can be enabled or disabled by the end user.

<figure><img src="/files/fzRcMg1gwwWKQG7kQa12" alt="" width="563"><figcaption><p>End-user settings for the default payment application</p></figcaption></figure>

If your application receives the NFC launch events below when the end user performs a double-click or field-detect action, it indicates that your payment application is set as the default payment application.

{% code expandable="true" %}

```swift
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
        
    // to support initiate contactless payments by double-click or field-detect action 
    // when application is not running + application is the default payment application
    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        
        if #available(iOS 17.4, *) {
            if let nfcEvent = connectionOptions.nfcEvent {
                switch nfcEvent {
                case .presentation:
                    // use case for double-click
                    break
                case .readerDetected:
                    // use case for field-detect
                    break
                @unknown default: break
                }
            }
        }
    }

}


extension SceneDelegate: NFCWindowSceneDelegate {
    @available(iOS 17.4, *)
    // to support initiate contactless payments by double-click or field-detect action when application is background or foreground and is the default payment application
    func windowScene(_ windowScene: UIWindowScene, didReceiveNFCWindowSceneEvent event: NFCWindowSceneEvent) {
        switch event {
        case .presentation:
            // use case for double-click
            break
        case .readerDetected:
            // use case for field-detect
            break
        @unknown default: break
        }
    }
}
```

{% endcode %}

{% hint style="info" %}
You can still perform a contactless payment when the application is not set as the default payment application. However, a double-click or field-detect action may bring the default application to the foreground.
{% endhint %}


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