Tap Payments' iOS checkout SDK. Present a full Tap checkout sheet from your app, collect a card or local payment method, and get the result back through a small delegate.

• Requirements
• How it works
• Installation
• Info.plist
• Quick start
• Callbacks
• Configuration reference
• Charge vs Authorize
• Sandbox vs production
• Example apps
• Troubleshooting

sequenceDiagram
    participant A as Your app
    participant T as Tap
    participant C as Checkout-IOS

    A->>T: Register your bundle id
    T-->>A: Public key
    A->>C: CheckoutSDK().start(configurations:delegate:)
    C-->>A: onReady()
    C-->>A: onChargeCreated(data:)
    C-->>A: onSuccess(data:) / onError(data:) / onClose()

In Xcode choose File > Add Package Dependencies... and enter:

https://github.com/Tap-Payments/Checkout-IOS.git

Select the Checkout-IOS product and add it to your app target. Or, in Package.swift:

dependencies: [
    .package(url: "https://github.com/Tap-Payments/Checkout-IOS.git", from: "1.0.5")
],
targets: [
    .target(name: "YourApp", dependencies: [
        .product(name: "Checkout-IOS", package: "Checkout-IOS")
    ])
]

Then import the module (note the underscore):

import Checkout_IOS

platform :ios, '15.0'

target 'YourApp' do
  use_frameworks!
  pod 'Checkout-IOS', '~> 1.0.5'
end

pod install

Open the generated .xcworkspace, not the .xcodeproj.

post_install do |installer|
  installer.pods_project.targets.each do |target|
    target.build_configurations.each do |config|
      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '15.0'
    end
  end
end

Add a camera usage description. It is required by the card scanner; without it iOS terminates the app when the scanner opens.

<key>NSCameraUsageDescription</key>
<string>Used to scan your card.</string>

1. Build a configuration dictionary.
2. Implement CheckoutSDKDelegate.
3. Call CheckoutSDK().start(configurations:delegate:).

import UIKit
import Checkout_IOS

final class CheckoutViewController: UIViewController, CheckoutSDKDelegate {

    // CheckoutSDKDelegate: the controller the checkout sheet is presented from.
    var controller: UIViewController { self }

    @IBAction func payTapped(_ sender: Any) {
        let configurations: [String: Any] = [
            "gateway": ["publicKey": "pk_test_YOUR_PUBLIC_KEY"],
            "language": "en",
            "themeMode": "light",
            "paymentType": "ALL",
            "supportedPaymentMethods": "ALL",
            "supportedCurrencies": "ALL",
            "selectedCurrency": "KWD",
            "amount": 5,
            "customer": [
                "firstName": "Jane",
                "lastName": "Doe",
                "email": "[email protected]",
                "phone": ["countryCode": "965", "number": "55567890"]
            ],
            "order": [
                "currency": "KWD",
                "amount": 5,
                "items": [
                    ["name": "Item", "description": "Item description",
                     "quantity": 1, "amount": 5, "currency": "KWD"]
                ]
            ],
            "transaction": [
                "mode": "charge",
                "charge": [
                    "saveCard": true,
                    "threeDSecure": true,
                    "redirect": ["url": "https://example.com/checkout/return"]
                ]
            ]
        ]

        CheckoutSDK().start(configurations: configurations, delegate: self)
    }

    // MARK: CheckoutSDKDelegate
    func onReady() { }
    func onChargeCreated(data: String) { print("charge created:", data) }
    func onSuccess(data: String) { print("success:", data) }
    func onError(data: String) { print("error:", data) }
    func onClose() { }
}

All five methods of CheckoutSDKDelegate are required. The data argument is a JSON string produced by the checkout; parse it with JSONSerialization or JSONDecoder.

The configuration is a [String: Any] dictionary that mirrors the Tap web checkout demo. Dotted paths mean nested dictionaries (gateway.publicKey is ["gateway": ["publicKey": ...]]). Defaults are the values the example apps send, which match the web demo; "omit" means the key is not sent. The SDK reads only gateway.publicKey and language itself; everything else is forwarded to the Tap backend.

<mode> is the value of transaction.mode.

transaction.mode decides what the checkout creates:

• charge: payment is captured immediately.
• authorize: funds are reserved and captured or voided later.

The settings for the transaction live in a sub-object named after the mode: transaction.charge for charges, transaction.authorize for authorizations. The inner fields are identical; only the key name changes. Use exactly one.

For authorizations, auto controls what happens if you do nothing:

• auto.type: CAPTURE captures the authorization automatically, VOID releases it.
• auto.time: hours to wait before that automatic action is applied (100 in the web demo).

Charge

{
  "transaction": {
    "mode": "charge",
    "charge": {
      "saveCard": true,
      "threeDSecure": true,
      "redirect": { "url": "https://example.com/checkout/return" }
    }
  }
}

Authorize

{
  "transaction": {
    "mode": "authorize",
    "authorize": {
      "saveCard": true,
      "threeDSecure": true,
      "auto": { "type": "VOID", "time": 100 },
      "redirect": { "url": "https://example.com/checkout/return" }
    }
  }
}

The SDK itself handles both modes the same way and fires the same callbacks. To capture or void an authorization manually, call the Tap API from your server using the authorization id returned in the callback payload. See developers.tap.company.

• Switch environments by changing gateway.publicKey. The Tap backend picks sandbox or production from the key.
• Use only your public key in the app. Never embed a secret key (sk_...) in a mobile binary.
• hashString must be generated on your server and passed to the app. Follow the Tap documentation for how to compute it; do not compute it with a secret key on the device.
• Keep keys out of source control: load them from build configuration or a remote config, not hard-coded literals in committed files.

Two minimal apps live in this repository.

Both include a Settings screen that mirrors every input of the Tap web demo and a Show configuration JSON view that prints the exact dictionary passed to start.

Before running, open Keys.swift and replace the placeholder YOUR_TAP_PUBLIC_KEY with your own Tap public key. Keys are not committed to the repository.

Sandbox test card (3D Secure)