Klarna On-site messaging is a free, public app on the Shopify app store. Before messaging Klarna in your Shopify store, first integrate Klarna as a payment method in your store.
Prerequisite: Prior to messaging Klarna on your storefront using the Klarna On-site messaging app, Shopify merchants should first integrate Klarna in checkout.
If you don’t yet have Klarna API credentials, you can sign up at http://klarna.com/business
Once you have received your Klarna API credentials, instructions to activate Klarna Payments in your Shopify store are available at the Klarna Payments on Shopify section.
This On-site messaging app can be used for any Shopify + Klarna integration using a Shopify theme (e.g. direct, Shopify Payments, Mollie, etc.).
There is a video of this app's integration and functionality available at: https://apps.shopify.com/klarna-on-site-messaging