Looks like Codling Moth damage - natural control methods include nematode sprays and pheremone traps, but there are some chemicals you can use - all have to be used at the right time, and that varies between treatments. Information below

https://www.rhs.org.uk/advice/Profile?pid=489

The bruising on the edge is caused by the fall of the apple . The problem is in the centre.

Thank you Bamboo you are always a great help.

The reason there is no sign of the pest is that the larva has left the building! It will now pupate in the soil at the base of the tree and change into a moth and infect the tree again. You need to spray with a Horticultural soft soap in February/March to kill any of them overwintering in the bark of the tree.

I think grease bands will also trap the adults as they try to climb up the bark. or am I thinking of a solution to another pest. definitely codling moth damage.

The grease bands actually are used to trap the moth larva as they travel DOWN the tree to pupate. They fly up as moths.
Also grease bands stop ants using the tree as a larder for aphids.

I never seem to know which way is up haha ! thanks for clarifying my half formed thought Owd :o)

Sorry Oldbuggy, & Seaburngirl, for not getting back to ye. I have not got back to the page as Anne and myself as we were keep busy looking after our grandson Charlie age 5 as his mother was finishing of her exams for nursing.

Thank ye all for the helpful advice. I was dreading the thought of climbing tree to harvest, but the gale force wind we had sorted that problem out for me. About 80% of the apples came down with the wind which was a few hundred apples. The damaged caused by the moth was not as bad as I first though it would be.