Google Calendar on Android has been manual entry and update more or less. With the latest update, Google has set out to build a smart assistant that’s always at your service. This includes turning emails into events automatically. Basically, Google Calendar has become an extension to Google Now, which was doing most of these stuff without actually updating your calendar. Busy professionals do share their calendar for others to check and schedule the meetings appropriately, so this can be extremely useful for such scenarios. In order to make things easier for things where it still needs manual intervention, Google Calendar app can now suggest titles, people and places as you type, as well as adapt to your preferences over time. Google calls this Assist (pretty appropriate).
Also, keeping in the latest image heavy design trends, the Calendar app carries a refreshingly new Schedule view that includes photos and maps of the places you’re going, cityscapes of travel destinations, and illustrations of everyday events like dinner, drinks and yoga. The new Calendar app will work on all devices running Android 4.1 and above, with the iPhone version being in works, and as always the rollout will happen in a phased manner, so note that it might take a while before you actually see the updated app in the Play Store.