Well, it’s sort of about context menus but different.
It’s all about using the contextual action mode. This lets the user do stuff with the items that they have selected.
Enabling the contextual action mode, displays a Contextual Action Bar at the top of the screen. You can then place action items, which are like menu options, on this bar.
The user selects items from a list for example, chooses an action item and the action linked to that action item is performed on all of the selected items.
Say you had a list of countries and you want the user to be able to select a couple of them to add to a database. This is where you could use the contextual action mode.
It enables the user to select one or more of the countries in the list. They can then select a Save action item, for example, and all the selected country items will be saved in the database.