The AppNav card zone scrolls. When you have more cards than comfortably fit in the zone it gives you a drop-down button. You can also collapse the window on both the Grid and the Planner to hide the cards completely. See the image below that shows an expanded set of cards at the top and the zone collapse button which appears on the Page Controls of the Grid and the Planner. 

The position of the cards is also determined by the user because you can drag and drop them in any order you wish and you will always log in to the top-left AppNav card, so you determine what is most important to you.