All of the names are cannon...Dr.Hooves (the most official name) is verified in the app. Dr. Whooves which is the same but gives a little more of a hint about hime being the 10th doctor. And time turner, verified in his collectable card. Because they made Derpy named Derpy Hooves so that she wouldn't be named ditzy doo and she was in a romance with the Doctor his official name is Hooves. Although Whooves is allowed, the same thing just spelled differently, and more widely used. He is married to derpy.