LiveGuideStep 3: Create an orderCreating an order differs for one-time and recurring payments. For one-time, send a POST with authorization token to Klarna. For recurring, generate a customer token first. GuideIntegrate one-step Express checkoutLearn how to integrate the one-step Express checkout for a fast and simple shopping journey. GuidePrepare your integration in-storeLearn about the prerequisites to enable Klarna Payments in your physical store. GuideIntegration optionsNow that you're ready to use Order management, learn the different integration options. GuideCustomize placements with CSSThis guide provides instructions on how to style the On-site messaging placements that appear on your pages through CSS to align them with the look and feel of your page. GuideCustomize placements through Merchant portalIf you're not familiar with CSS or don't have access to your website's source code, use Klarna's Merchant portal to customize placements to better suit your website's design. GuideMerchant Portal - SettingsKlarna Portal offers tools for managing account credentials and details, including generating/disabling API keys, creating client identifiers for web integration, and updating SFTP credentials, bank, and customer service info. GuideHosted Payment Page - iOSIf the recommended integration approach of Klarna Mobile SDK is not possible, the guide below will guide you through how to integrate the Hosted Payment Page in your mobile app without the Mobile SDK. GuideStep 1: Initiate a paymentThis section of the guide walks you through initiating a payment and letting your customers pay with Klarna. GuideStep 2: CheckoutLearn how to set up the Javascript SDK to display Klarna's widget. GuideMixed paymentsLearn more about Mixed payments here. GuideSubscriptions and on-demand on Klarna PaymentEverything you need to know about subscription and on-demand use cases. GuideOn-site messaging JavaScript libraryThe JavaScript library delivers the core functionality of On-site messaging. GuideKlarna Docs - Choose your integration for MobileIntegrate Klarna into your mobile app using the Klarna Mobile SDK, choosing between native or WebView options to balance seamless user experience with flexibility and security. GuideAuthorization callbackTo ensure optimization of the conversion rates, you should get an authorization token through a server-side callback. 