Hello,

This appears to be sooty blotch. You should be able to wipe the spots off. Sooty blotch is  a fungal disease that affects the skin of apples, but will not cause rot. It's typically prevented by the use of fungicides in the summer, though it can be culturally managed by pruning the tree to allow for greater air circulation in the canopy. Here are a brief article and a fact sheet about the disease from MSU Extension.