There aren’t very many differences between version 6.0 and the older version. Google Material Design UI often includes bright colours and whites. However, the Calendar app was pretty much already like that.
Users can now quickly tap a small arrow beside ‘September’ (seen above) to get a quick glimpse of the whole month. The plus icon allows users to add events, while on the bottom right corner is a multi-coloured instead of just red. Additionally, tapping the menu button shows an assortment of Material Design themed icons.
To see other apps that have received Google’s Material Design update, click here.
Source: Android Police