Start by peeling and cutting up the 4 large apples, into bite-sized pieces.
Then mix together the 1 1/4 cup granulated sugar 2 tablespoons cornstarch 1 teaspoon ground cinnamon, 1/2 teaspoon ground nutmeg, 1/2 teaspoon allspice and 1/4 cup water into a small saucepan. Mix well.
Bring to a small simmer, and then turn off the heat.
Remove from heat and then mix in the 4 tablespoons butter, apples, and1 teaspoon lemon juice. Meanwhile, blend all of the topping ingredients into a small bowl, and mix well.
Pour the filling into a greased baking pan. Scatter the topping on top of the filling.
Set the pan into the air fryer basket.
Set the air fryer temperature to 320 degrees F, air fryer setting, and set cook time for 12-15 minutes, or until the pie is fully cooked, and golden brown.