Start by washing the apples, and then drying them with a paper towel or clean kitchen towel. Preheat your air fryer to 150 degrees F, using the air fryer setting.
Using a sharp knife or mandoline slicer, cut the whole apples, into either thin slices, or apple rings, you can either peel the apples or leave the peel on.
Add the sliced apples into a large bowl, and then add the ground cinnamon, toss well to coat the apples.
Add the apple slices to the bottom of the air fryer basket, in a single layer, and set the cooking time to 15-20 minutes, at 150 degrees F, every few minutes use a large fork and flip the apple slices.
Depending on the size of your air fryer, you may need to cook these apples in batches.
Transfer the dehydrated apples to a wire rack, or cooling rack and let them cool, before serving.