This appears to be apple core rot, which can be caused by a variety of fungal pathogens. This can be exacerbated by early ripening, especially as apples soften, and even accelerate the senescence and dropping of apples as a stress response. The warm and wet weather we had early in the season combined with early bloom pushed apple maturity 10-14 days ahead of normal this year. Fungal pressure seems to have increased the stress on your trees.

Without a picture I can't say what might be the cause of the leaves, but the most common fungal disease in apples is apple scab. Early season fungal control and removal of infected leaves and fruit from the orchard in the off-season will help reduce inoculum and prevent additional infection.