Put the apples in a large zip top bag and add ½ cup white sugar, ½ teaspoon of cinnamon and 1 ½ teaspoons of flour. Zip bag and shake to coat all the apples evenly.
Pour the coated apples into a pie pan.
To make the topping, combine brown sugar, flour, oats, baking soda, baking powder, and nutmeg in a bowl. Add the melted butter and mix until crumbs are formed.