I have seen a number of videos and pics where the photographer has said 'use your phone upside down'. No one said why you use it upside down - but, it is all a matter of point of view. If you turn the phone upside down the lens is at the bottom of the phone so you can get a closer viewpoint of your subject. The macro lens on my mobile phone was used to capture the truck reasonably in focus and the background out of focus. I also like how well the pattern of the tablecloth can be seen.
