Pour the apple pie filling into your crockpot. Sprinkle with 1/2 tsp cinnamon and mix in to combine.
Mix the remaining cinnamon in with the dry cake mix in a separate bowl. Sprinkle over the apples. Drizzle the melted butter over the cake mix, evenly. Do NOT mix the butter into the cake mix.
Cover and Cook on high for 4 hours - or on low for 6 hours.
Serve with a scoop of vanilla ice cream, if desired.