Blue, purple potatoes -same thing. In the south people will quietly ask 50 times who made the tater salad before ever approaching the bowl and lifting the spoon. Reckon my current favorite is a grocery store deli loaded baked potato salad that I add purple potato a purple onion and see thru slices of purple or black garlic. My potato salad is like most everything else I do, edible but not repeatable.
https://www.bonappetit.com/recipes/slideshow/potato-salad-recipe-slideshow
https://www.bonappetit.com/recipes/slideshow/potato-salad-recipe-slideshow