Say man how are you taking picks of your shoes like that?^
I have a rubber case on my iPhone so I do this two ways....
-bend a bit and have one side of the phone against the floor and my hand on the shutter. I usually have it set on the self facing side so I can see if the shoes are centered.
-if it's a floor where the phone can stand on its side without falling I'll just use a camera app with a self timer (I use Camera +)
-I usually edit in Snapseed and add the tilt shift for the focus affect