Preheat oven to 350 degrees F. Lightly grease a 9x13 or 11x7 inch baking dish with nonstick cooking spray and set aside.
In a large bowl, combine apples with lemon juice, flour, granulated sugar and ½ teaspoon cinnamon. Pour into the baking dish and spread evenly.
In a medium sized mixing bowl, combine rolled oats, flour, brown sugar and salt. Using a pastry cutter or your fingers, cut in the butter until small, pea-sized lumps form and no flour is visible. Sprinkle this mixture evenly over the apples.
In a small dish, combine 2 tablespoons granulated sugar with 1 teaspoon cinnamon. Sprinkle over the top of the crumble.
Bake in the prepared oven for 45 minutes, rotating a quarter turn about halfway through.
Cool slightly before serving.