For a great pie, you need a fairly large amount of apples that hold their shape during baking along with a smaller number of soft apples that fall apart and serve to unify the rest. The list includes common varieties but to test yourself, just saute the slices and see if they stay firm or fall apart.
Apples that hold their shape - Braeburn, Golden Delicious, Granny Smith, Jonagold, Rome Beauty, Winesap (Stayman)
Apples that soften - Cortland, Empire, Macoun, McIntosh.
Apples not recommended for pies - Fuji and Red Delicious.