That looks like apple scab, a fungal pathogen that is common in this region. Scab starts as olive or brown velvet-like spots on leave. The spots become darker and larger as they progress, and typically form along the veins of leaves. The diseased leaves may be curled and distorted, and often drop early. Symptoms on the fruit appear as dark spots that can take on a cork-like appearance. Severely infected fruit may crack or become deformed.

In the fall, rake up and destroy (burn or bury) fallen leaves, the fungus overwinters on fallen diseased leaves. During the dormant season, prune the tree to open it up and allow for good air flow through the canopy so that the leaves dry quickly after a rain. Avoid using overhead irrigation (e.g. sprinklers) that wet the foliage of the tree, use drip or hand water instead. There are a number of fungicides that are registered for home use, but they are not curative, they will only protect new healthy leaves from becoming infected. Fungicides need to be applied early in the season as soon as the green tips start to emerge from the buds in the spring. For more on apple scab, see http://hortsense.cahnrs.wsu.edu/Search/MainMenuWithFactSheet.aspx?CategoryId=3&PlantDefId=59&ProblemId=15#:~:text=Apple%20scab%20is%20caused%20by,olive%2Dgreen%20then%20to%20black. For a schedule of pest management activities for apples, including scab, refer to: https://catalog.extension.oregonstate.edu/ec631