We have had an apple tree that produces TONS of fruit. By trial and error, I found how to produce larger, better fruit.
Step 1: Prune
The trick is to start picking bad apples when the fruit is still small, but large enough to see contamination. In our area, that usually requires starting in July.
Pick all the bad fruit as soon as it has visible marks of infestation. Not all, but most times when there is deformity, it is because of bugs.
I was really excited to find a farmer that loved to feed the bad fruit to his pigs. Sometimes people even feed bad fruit to horses. This is an excellent way to use that "protein-enhanced" fruit.
Step 2: Healed Blemishes
Sometimes a blemish heals over and the result is fruit that is still good.
Step 3: Birds
Birds like fruit too, and I sometimes feel like a fast food joint for birds.
That fruit might still usable for apple sauce or juice because birds do not cause the contamination that bugs do.
Step 4: Harvest
The result is a harvest of large, clean apples! We use ours for pie filling, apple sauce and juice.