This document discusses smart app banners, which allow websites to display a button prompting users to install or open an app from the app store. The meta tag code for smart app banners includes the app ID, affiliate data, and a URL. If the user is on an iOS device in a supported country, the banner will link directly to the app store listing. The banner also allows affiliate tracking by including affiliate data in the URL. Smart app banners provide a friendly user experience by explaining what will happen when the user clicks the download or open button.