Your checkout screen when Klarna is selected as payment method.	Hosted Payment Page flow starts when customer confirms to Continue with Klarna.	Your order confirmation screen after a successful payment.

Integration Steps

• Prepare: Make sure you have a web checkout integrated with Klarna Payments.
• Set up your app (Mobile App): Set up return URL to your application.
• Present your web checkout (Mobile App): Present you web checkout using System WebView.

This guide will lead you through all the steps required to accept Klarna Payments in your mobile app using your web integration. At the end, you will be able to accept payments with Klarna with very few native changes.

Klarna purchase flows might require authorizations in other applications (e.g. bank apps) or do a handover to the Klarna app. In such cases, a return URL to your application ensures seamless return to the flow in your app, hence setting up a return URL is required. It is expected that redirects to this URL should only open your application without any changes in the UI state, ensuring the customer can continue the flow prior to external navigation.

You can set up a Return URL app scheme to your application by configuring a custom URL scheme.

To avoid a Klarna specific app scheme, you can use a host in a common scheme for Klarna redirects, e.g. myApp://klarna-redirect , this can allow you to differentiate and handle these redirect in your handler.

Considering the return URL is a constant value in Constants.klarnaReturnUrl, you can handle redirects to your return URL as such:

On iOS, system WebViews are typically implemented using ASWebAuthenticationSession or SFSafariViewController. While they appear similar from the customer's perspective, they differ significantly in how they handle session and cookie management.

ASWebAuthenticationSession supports cookie and session sharing with the Safari browser by default. This capability is crucial for Klarna, as it allows us to recognize returning customers across the device and deliver a smoother checkout experience.In contrast, SFSafariViewController does not support session persistence or cookie sharing.

Therefore, we require the use of ASWebAuthenticationSession with prefersEphemeralWebBrowserSession set to false, ensuring sessions are persistent and shared with Safari.

Start ASWebAuthenticationSession with your web checkout URL for this customer session:

let session: ASWebAuthenticationSession = ASWebAuthenticationSession(
    url: sessionUrl, // URL of your web checkout
    callbackURLScheme: callbackUrl // your completion for closing the System WebView from your confirmation page
) { url, error in
    guard error == nil else {
        // Handle error
        return
    }
    
    guard let url = url else {

Implement ASWebAuthenticationPresentationContextProviding to provide a ASPresentationAnchor to the session:

extension YourViewController: ASWebAuthenticationPresentationContextProviding {
    func presentationAnchor(for session: ASWebAuthenticationSession) -> ASPresentationAnchor {
        return self.view.window ?? ASPresentationAnchor()
    }
}

Enabling shared cookies and device wide single login experience for System WebView will result in user accepting to allow login via "<yourdomain>.com" on iOS. This is a common practice, and we expect almost all iOS users to be familiar with it and accept accordingly.

Redirect back to your app

After the purchase is completed, Klarna payment flow will be closed and the customer will be taken back to your checkout page where you will be notified for the authorized session in your web integration. From your checkout or the confirmation page, you can choose to redirect the customer back to your application.

To get the user back to your application from System WebViews, you can redirect to callbackURLScheme set for ASWebAuthenticationSession from your checkout or confirmation pages, as those will be loaded in the System WebView.

Klarna purchase flow in System WebView.	Your checkout page in System WebView.	Your confirmation page in System WebView.

Klarna Mobile SDK provides a full suite of mobile-first integrations, including Klarna products like:

Sign in with Klarna	On-site Messaging	Express Checkout

• On-site Messaging: Show contextual messaging let your customers know about the available payment options in pre-checkout: click here to learn more.
• Sign in with Klarna: Seamlessly identify and let users login via their Klarna account: click here to learn more.
• Express Checkout: Accelerate your checkout process and boost conversion by offering a one-click checkout, click here to learn more.

Complete your integration with

• Order management
• Settlements
• End-to-end testing
• Prepare for go live