For their Blogger (blogspot.com) blog, Google added a "built-in "stats" tab on the draft dashboard, that lets you see real-time data about a blog: "most popular posts, number of pageviews for each post, total number of pageviews, list of traffic sources and search keywords, breakdown of pageviews by country, browser & operating system. Of course, traffic data across longer time periods (day/week/month) and all-time historical data are available as well.
Stats shows all of this data in a simple, easy-to-understand graphical user interface. You don't have to install or configure anything to start benefitting from Stats.
For e.g., if one of your post is shared on Twitter and getting lots of clicks, you'll see traffic increase in Blogger Stats almost instantly, with particular Tweet mentioning your post being identified as the traffic source," explains Google.