Wash apples and dry thoroughly. Insert a wooden skewer in stem end of each apple. Spray plate with cooking spray.
In 2-quart saucepan, mix sugar, corn syrup, milk and salt. Cook over low heat, stirring constantly, to 230°F on candy thermometer or until a few drops of syrup dropped into cup of cold water forms a soft ball that flattens when removed from water. Remove from heat; stir in vanilla. Cool slightly.
Quickly dip apples into caramel, swirling until completely covered. Dip bottoms in candy sprinkles. Place apples on plate until caramel is set.