Hi, I have a desktop app and I communicate with many webstores, I prefer XML (or JSON) to transfer data between my app and the webstores.
here is example of one google platform for webshops: https://devdocs.prestashop.com/1.7/webservice/
Images: https://devdocs.prestashop.com/1.7/webservice/tutorials/advanced-use/image-management/