1. Preheat oven to 350°F (175°C). In a bowl, mix graham cracker crumbs, melted butter, and granulated sugar. Press into the bottom of a springform pan.
2. In another bowl, beat cream cheese until smooth. Add sour cream and eggs one at a time; mix until fluffy. Stir in sugar and spices.
3. Pour half the cheesecake batter into the crust; layer with sliced apples. Top with remaining batter.
4. In a small bowl, combine oats, brown sugar, more melted butter, cinnamon, and nutmeg. Sprinkle over the cheesecake.
5. Bake for 50-60 minutes or until edges are set but center jiggles slightly. Cool at room temperature before refrigerating for at least four hours.
6. Serve chilled with caramel sauce if desired.
