This was an early concept for the visual design refresh. I'm still a big fan of apps presenting a menu at the start, which clearly tells the user all the features of the app. No need to "discover" them in nav drawers or explore icons that open menus.
I had some cool animations that slide the menu down and up again as you navigate the menu tabs.
None-the-less, I settled on a different design and never used this concept, although I might use it in another app one day.