Apples are funny. They can't grow from seed. They are "created" from crossing the genetic material of two different kinds of trees so that may make their needs a bit different, but here is a simple write-up on their cross-pollination. We do have two different types of tress on our property, though at my previous home the two trees produced very similar fruit so I guess I always assumed they were the same type of tree, but maybe they are just different enough. :-D
Okay so it would be a good idea to make sure there are honeybees close by. I have considered raising honeybees when I get my property anyways. It is a little intimidating because I don't like to get stung LOL