For apple pie you want to use pretty firm apples so that they will keep their shape and some texture when baking. Other than that, it's mostly a matter of taste. Since this puff pastry apple pie doesn't have any sugar in the dough a sweeter apple is great, but you do you. Great, firmer, options for apples are Gala, Ingrid Marie, Granny Smith, Jazz, Pink Lady, Honey Crisp, Golden Delicious, Jonagold and Northern Spy.