Google analytics for ECommerce, enables the measurement of user interactions with products on ecommerce websites across the user's shopping experience, including: product impressions, product clicks, viewing product details, adding a product to a shopping cart, initiating the checkout process, transactions, and refunds.
Free service that generates a social sharing buttons script. You choose the desired buttons by your own.
Sites who has this tag are verfied by google to use WebMaster tools
When running in a browser on a mobile phone, "format-detection" meta tag determines whether or not telephone numbers in the HTML content will appear as hypertext links. The user can click a link with a telephone number to initiate a phone call to that phone number.