1. In a small bowl, dissolve yeast in warm water and set aside.
2. In a large mixing bowl, combine sugar, milk, melted butter, salt, and 2 cups of flour. Mix well.
3. Add yeast mixture to the bowl and mix. Add remaining flour, ½ cup at a time, until dough is no longer sticky. Knead for 5 minutes.
4. Place dough in a greased bowl, cover, and let rise until doubled in size, about 1 hour.
5. Preheat oven to 375°F (190°C). Roll out dough on a floured surface into a rectangle.
6. Spread softened butter over the dough. Sprinkle brown sugar, cinnamon, and chopped apples evenly over the butter.
7. Roll up dough tightly and cut into 12 rolls. Place rolls in a greased baking dish.
8. Bake for 25 minutes or until golden brown. Serve warm.