My parents have a crabapple tree on their farm, its actually in their front yard. In aug/sept I watch deer eating the apples every evening. You can see the line of how high they can reach to get them off the tree, then they eat the ones that drop.

I planted 15 crabapple trees on the family farm last year in hopes of having a nice orchard in a few years. I'm going to keep them well fertilized