Warm the tortillas in a microwave to make them pliable. Spread each tortilla with 1 tablespoon of peanut butter. Divide the apple filling between the 4 tortillas. Fold in sides and then roll up each tortilla. Transfer to an ungreased baking sheet and make a couple of slashes in the top to allow the steam to vent. Sprinkle the tops of tortillas with 1 tablespoon sugar and bake until lightly browned, about 10 minutes. Remove from the oven and put the tortillas on a serving platter.
In a small bowl, whisk together the cream cheese, milk, powdered sugar, and pumpkin pie spice. Brush on the apple pies and serve.