My 'Anna' apple has finished fruiting now. It gave a good crop considering it was planted only last year. Most of the apples were very good - good size, firm, sweet and crisp. The leaves are still very healthy, as they have been all season. When ripening, the first fruit to show red were pecked by magpies (in between having my tomatoes), but they gave up on that, thankfully. But around the same time, some of the near-ripe fruit developed brownish patches. There was no sunkeness or swelling and no hint of damage to the skin by insects or bruising.
So it is not a big problem, but I am curious to know the cause.
The photos may be more enlightening than my description - showing the browning to be concentrated just below the surface.
Regards,
Mike