Open both cans of filling, I've had more luck by adding the apple first since it's thicker to one side of the slow cooker. Add the cherry pie filing next.
In a medium-sized bowl mix together the cake mix, melted butter, egg, vanilla and salt. I add this on top of the pie fillings by spoonfuls, then I spread it out evenly.
In a small bowl mix together the cinnamon and sugar. Sprinkle over the cobbler.
Cover and cook on HIGH for 2 hours 15 minutes to 2 hours 30 minutes. Keep the lid on the entire cooking time. The cobbler will be done when the center is set.
Serve and enjoy!
Video
Notes
Other pie filling options other than apple and cherry (use 21-ounce cans of PIE FILLING not fruit in thin juices):