Pay by App button

The MPPayByApp view lets the customer pay through their bank's mobile app rather than entering card details in your app. The view discovers installed bank apps via their published deep-link schemes; the customer picks one; Scan to PayKit deep-links into that app to complete payment.

For the pure card-in-SDK flow, see Pay-by-Card button.

Prerequisite — LSApplicationQueriesSchemes

Before iOS will let you check whether bank apps are installed, you must declare their schemes in Info.plist:

<key>LSApplicationQueriesSchemes</key>
<array>
    <string>masterpass.absa.scheme</string>
    <string>masterpass.sbsa.scheme</string>
    <string>masterpass.nedbank.scheme</string>
    <string>masterpass.spenda.scheme</string>
    <string>masterpass.capitec.scheme</string>
    <string>masterpass.vodapay.scheme</string>
    <string>nedbank</string>
    <string>https://www.online.fnb.co.za/banking/mobileservices?codetype=masterpassdeeplink</string>
</array>

Without these entries, canOpenURL(_:) returns false even for installed apps — iOS treats omitted schemes as "not installed" for privacy reasons.

Adding the view via Storyboard

Drag a UIView onto your storyboard
Constrain it where you want the button to sit
Open the Identity Inspector and set the Custom Class to MPPayByApp
Wire an @IBOutlet in your view controller

@IBOutlet weak var payByApp: MPPayByApp!

Set the delegate in viewDidLoad:

override func viewDidLoad() {
    super.viewDidLoad()
    payByApp.delegate = self
}

Handling the tap

Adopt MPPayByAppDelegate and implement didPayByApp(withInfo:). The appInfo dictionary tells the SDK which bank app the customer chose:

extension CheckoutViewController: MPPayByAppDelegate, MPMasterPassDelegate {
    func didPayByApp(withInfo appInfo: [AnyHashable: Any]?) {
        view.endEditing(true)

        let apiKey  = "YOUR_API_KEY"
        let system  = MPSystem.test
        let qrCode  = "6799782555"

        let masterpass = MPMasterPass()
        masterpass.checkoutUsingPayByApp(withAPIKey: apiKey,
                                         system:     system,
                                         delegate:   self,
                                         withAppInfo: appInfo,
                                         application: UIApplication.shared,
                                         qrCode:      qrCode,
                                         andCallback: "your.app.scheme://")
    }
}

Parameters

Name	Type	Description
`apiKey`	`String`	Your Lib Lite API token from the Portal
`system`	`MPSystem`	`.live` or `.test`
`delegate`	`MPMasterPassDelegate`	Where the SDK calls back
`appInfo`	`[AnyHashable: Any]`	Routing info for the chosen bank app — passed through from the view's delegate callback
`application`	`UIApplication`	Used to launch the bank-app URL
`qrCode`	`String`	Transaction code from `/code` (fixed amount)
`andCallback`	`String`	Your app's callback URL scheme — the bank app uses it to return after payment

The andCallback value should match a URL scheme declared in your app's Info.plist:

<key>CFBundleURLTypes</key>
<array>
    <dict>
        <key>CFBundleURLSchemes</key>
        <array>
            <string>your.app.scheme</string>
        </array>
    </dict>
</array>

Result handling

The result comes back via the standard MPScanToPayDelegate / MPMasterPassDelegate callbacks. See Payments — same methods, same semantics.

Additionally, you'll need to handle the inbound URL when the bank app returns:

// In your AppDelegate or SceneDelegate
func application(_ app: UIApplication,
                 open url: URL,
                 options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
    // Pass through to the SDK if it's a Scan to Pay callback
    if url.scheme == "your.app.scheme" {
        // SDK handles this internally — the delegate methods will be called
        return true
    }
    return false
}

Supported bank apps

The view discovers bank apps using their published deep-link schemes:

Bank	Scheme
ABSA	`masterpass.absa.scheme`
Standard Bank	`masterpass.sbsa.scheme`
Nedbank	`masterpass.nedbank.scheme`
FNB	(URL-based, not a scheme)
Capitec	`masterpass.capitec.scheme`
VodaPay	`masterpass.vodapay.scheme`
Spenda	`masterpass.spenda.scheme`

Add or remove from LSApplicationQueriesSchemes to match which apps you want detected.

When no bank apps are installed

The view will be empty / hidden when no supported bank apps are detected. You should provide a fallback (a Pay-by-Card button next to it) so the customer can still pay.

What's next

Just want the card flow → Pay-by-Card button
The underlying checkout → Payments
Result codes → Errors
App-to-app from the merchant side → App-to-app