Preheat oven to 375 degrees. For filling, combine sugar, flour, and lemon peel in large bowl; mix well. Add lemon juice, apples, and cranberries; stir to mix. Spoon into 6-cup baking dish.
For topping, combine oats, brown sugar, flour and cinnamon in small bowl. Add melted butter and stir to mix. Sprinkle topping over filling. Bake for approximately 40-50 minutes or until filling is bubbly and top is brown. Serve warm or at room temperature with plain or vanilla yogurt. 6 servings.