Melt butter in a large skillet over medium heat. Add sweet potatoes; cover and cook over medium heat 5 minutes or until golden. Turn potato slices over. Reduce heat, cover, and cook 5 more minutes.
Remove potatoes from skillet. Add apples; cook 5 minutes on each side or until tender and golden.
Return potatoes to skillet. Add sugars, pecans, cinnamon, and salt, tossing to coat. Add 2 tablespoons water, stirring to loosen browned particles. Cook 5 minutes or until potatoes and apples are glazed and tender.