Preheat the oven to 200 F and line two baking sheets with parchment paper.
Thoroughly wash, dry, and core the apples, and slice them into ⅛-inch slices (use a mandolin if possible).
Place the apple slices on the baking sheets and brush them with lemon juice.
Sprinkle with cinnamon, and bake for one hour, placing the baking sheets on the middle racks.
Switch the position of the baking sheets, and bake for 1.5 hrs more.
Test the texture of the chips and let them bake for 10 more minutes if not crispy enough.
Turn the oven off and let the chips sit in the oven for 60 more minutes.