Quick Start

Video Tutorial: iOS SDK Integration

This video walks you step-by-step through the iOS SDK integration process. Watch it to quickly understand setup, configuration, and key features in action.

Installation

Minimum Requirements

Before integrating the Checkout SDK, please review the following requirements:

• Since the minimum supported iOS version is 14, the primary demo application is implemented using UIKit framework (SwiftUI is recommended starting from iOS 15). ottu-ios/Example at main · ottuco/ottu-ios

• However, there’s also a minimalistic SwiftUI-based demo app: ottu-ios/Example_SwiftUI at main · ottuco/ottu-ios

You can install the SDK via two paths:

• Swift Package Manager (Recommended)

• CocoaPods (Deprecated)

Installation with Swift Package Manager (Recommended)

Add Ottu SDK as a dependency in Package.swift:

dependencies: [
    .package(url: "https://github.com/ottuco/ottu-ios.git", from: "2.1.8")
]

Or in Xcode:

1. Open your project

2. Go to Project > Targets > Package Dependencies

3. Add ottu-ios as a dependency

Installation with CocoaPods (Deprecated)

Add the following line to your Podfile:

pod 'ottu_checkout_sdk', :git => 'https://github.com/ottuco/ottu-ios.git', :tag => '2.1.8'

Run:

pod install

When ottu_checkout_sdk is added to the Podfile, the GitHub repository must also be specified as follows:

pod 'ottu_checkout_sdk', :git => 'https://github.com/ottuco/ottu-ios'

If you see “could not find compatible versions for pod”, run:

pod repo update

SDK Configuration

Once the SDK is installed, follow these steps to integrate it into your app.

1

Import the SDK

In your ViewController.swift (or any file responsible for presenting the SDK):

import ottu_checkout_sdk

2

Conform to OttuDelegate

Your view controller must implement the OttuDelegate protocol:

class ViewController: UIViewController, OttuDelegate 

3

Declare a Checkout Member

Inside your ViewController

private var checkout: Checkout?

4

Initialize Checkout

Inside viewDidLoad, initialize the Checkout SDK:

do {
    self.checkout = try Checkout(
        displaySettings: PaymentOptionsDisplaySettings(
          mode: PaymentOptionsDisplaySettings.PaymentOptionsDisplayMode.list,
        ),
        sessionId: sessionId,
        merchantId: merchantId,
        apiKey: apiKey,
        delegate: self
    )
} catch let error as LocalizedError {
    print(error)
    return
} catch {
    print("Unexpected error: \(error)")
    return
}

Required parameters

• sessionId → ID of the created transaction

• merchantId → Same as the domain address in API requests

• apiKey → Public API key for authorization

• delegate → Callback listener (usually self)

Recommended parameters

• formsOfPayment → Defines available payment methods

• setupPreload → Preloads transaction details for faster initialization

setupPreload comes from the transaction creation response. Passing it prevents the SDK from re-fetching transaction details, reducing initialization time by several seconds. It is a decoded JSON object to a TransactionDetails object. See an example: MainViewController.swift

The simplest version of the initialization looks like this:

do {
    self.checkout =
        try Checkout(
            sessionId: sessionId,
            merchantId: merchantId,
            apiKey: apiKey,
            delegate: self
        )
} catch
let error as LocalizedError {
    // display an error here
    return
} catch {
    print("Unexpected error: \(error)")
    return
}

5

Add the Payment View

Still inside viewDidLoad, embed the payment view into your container:

if let paymentVC = self.checkout?.paymentViewController(),
    let paymentView = paymentVC.view {

        self.addChild(paymentVC)
        paymentVC.didMove(toParent: self)
        view.addSubview(paymentView)
    }

This is a basic example that adds the Checkout view without handling dimensions. For proper layout with constraints, refer to the demo app: OttuPaymentsViewController.swift

Callbacks

In order ViewController to be compliant to OttuDelegate, add the following functions to ViewController class:

func errorCallback(_ data: [String : Any]?) {
    navigationController?.popViewController(animated: true)
    let alert = UIAlertController(title: "Error", message: data?.debugDescription ?? "", preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "OK", style: .cancel))
    self.present(alert, animated: true)
}
    
func cancelCallback(_ data: [String : Any]?) {
    var message = ""
       
    if let paymentGatewayInfo = data?["payment_gateway_info"] as? [String : Any],
       let pgName = paymentGatewayInfo["pg_name"] as? String,
       pgName == "kpay" {
           message = paymentGatewayInfo["pg_response"].debugDescription
    } else {
        message = data?.debugDescription ?? ""
    }
        
    navigationController?.popViewController(animated: true)
    let alert = UIAlertController(title: "Canсel", message: message, preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "OK", style: .cancel))
    self.present(alert, animated: true)
}
   
func successCallback(_ data: [String : Any]?) {
    navigationController?.popViewController(animated: true)
    let alert = UIAlertController(title: "Success", message: data?.debugDescription ?? "", preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "OK", style: .cancel))
    present(alert, animated: true)
}

• Error → Displays an error alert and navigates back

• Cancel → Displays cancel reason (custom handling for kpay)

• Success → Displays success confirmation

This code describes callbacks to be handled by the parent app.

Apple Pay

If your app should support Apple Pay:

1. Enable Apple Pay capability in: Xcode > Targets > Signing & Capabilities

2. Add Apple Pay Merchant IDs (MID) in project settings

Advanced Features

• Forms of Payment

• Customization Theme

• Setup Preload