Looks like the corking I get on my quince, it occurs widely on apples also; research cork spot or corking and apples.

A local expert thinks bitter pit or some stinkbugs. Corking and bitter pit is basically the same treatment. I'm almost leaning toward Stinkbugs...will have to look closer this year.

Could the apple on the left have Brown Core? I know I caused the problem for myself with stored apples a few years ago...

Not stink bugs. Their damage is discrete groups of dried/corky cells about one cm below the skin.

See this: http://jenny.tfrec.wsu.edu/opm/gallery.php?pn=190

Not bitter pit, either.

Damage is similar to that from stink bugs but is far more shallow, just below the skin.

>>Could the apple on the left have Brown Core?<<

I don't think so...been keeping them at the same temperature. Here a photo of the same apple [Norkent] in 2013 mid February...they've been spotless for years without spraying.