Preheat your oven to 325°F (160°C). Grease a 9-inch springform pan with cooking spray and set aside.
In a mixing bowl, combine the graham cracker crumbs, melted butter, and 1/4 cup sugar. Mix until the crumbs are evenly coated. Press the mixture firmly into the bottom of the springform pan to form a uniform layer. Bake for 8-10 minutes until golden, then let it cool slightly.
In a large bowl, beat the softened cream cheese with an electric mixer until smooth. Gradually add in 1 cup of sugar and continue beating. Mix in the vanilla extract, then add eggs one at a time, mixing on low speed until just combined.
In a separate bowl, toss the sliced apples with lemon juice and cinnamon. Gently fold the apple mixture into the cream cheese batter. Pour the mixture over the pre-baked crust, spreading evenly.
In another bowl, mix together the brown sugar, oats, flour, and salt. Add melted butter and mix until crumbly. Sprinkle the crumble topping evenly over the cheesecake filling.
Bake the cheesecake for 50-60 minutes, or until the center is set but slightly jiggly. The edges should appear firm. Turn off the oven and crack the door open, letting the cheesecake cool in the oven for about 1 hour to prevent cracking.
Once cooled, refrigerate the cheesecake for at least 4 hours, preferably overnight to set completely.
Carefully release the springform pan and slice the cheesecake. Serve chilled plain or with a dollop of whipped cream on top.