Preheat the oven to 375° F. Coat a 9×13 baking dish with the softened butter and set aside.
Start by peeling and cutting the apples into 1/4-in. slices. In a large bowl, whisk together the cranberry sauce, sugar and flour. Add the apples to the cranberry mixture and stir to coat all ingredients. Pour the mixture into the baking dish.
For the crumb topping, mix together oats, flour brown sugar, melted butter, pecans and cinnamon. Sprinkle mixture over the top.