For the apples I am not sure. My first question for you is do the apples crack first and then black/brown regions appear or is it the reverse where the black/brown regions appear and then the apples later crack?
It’s possible it’s a form of sunburn if the black/brown forms first or some Summer rot. If it cracks first it may be your growing conditions make the apples prone to cracking and a secondary infection forms on the cracked areas. In this case you need to find a way to reduce cracking.
Summer rots are often hard to distinguish from one and other. I would try to get some pictures of the affected fruits next year in the early, middle and late stages of the infection. Also take pictures of some of the fruits after you have cut them open since a cross section of the infection can be diagnostic in some cases.
In many cases, even if the infection isn’t identified more Summer sprays can help control the problem.
Here is a link to thread that can help you identify Summer rots and also suggests cultivars that have resistance to rotting.