Good luck on that. There are hundreds of apple cultivars.
If it were me, I'd poke around in the neighborhood and ask if anyone else has an apple tree. If they do, and if it looks at all like your tree, ask them if they know what cultivar their tree is.
I've got 6 apple
trees, and I know what variety they are. But just looking at them . . . no way I'd be able to tell you.
"The rule of no realm is mine. But all worthy things that are in peril as the world now stands, these are my care. And for my part, I shall not wholly fail in my task if anything that passes through this night can still grow fairer or bear fruit and flower again in days to come. For I too am a steward. Did you not know?" Gandolf