Horizontally rotate the Viewport in 180 degrees to see the back side? Is there an easy way to rotate the view horizontally to see the backside, as from the first picture to the second picture? 

I was following a phone modelling tutorial, and the guy jumped form the front side of the phone to the back side of the phone, but I couldn't find a way to do that. I have tried clicking combinations of the "X", "Y", "Z" circles on the top-right, but none of them resulted in the backside as the second picture. I can manually rotated the view using the middle mouse drag to end up as the second picture, but the axes are not perfectly aligned with the screen as the first picture, which was achieved by simply clicking the "Z" circle.
Numpad 7 is the shortcut for top view, Ctrl+Numpad 7 is the shortcut for bottom view.

Same for Numpad 1/Ctrl+Numpad 1 (front/back), Numpad 3/Ctrl+Numpad 3 (right/left)