Place the apples in a slow cooker. In a medium bowl, mix the sugar, cinnamon, cloves, and salt. Pour the mixture over the apples in the slow cooker and mix well. Cover and cook on high 1 hour. Reduce heat to low and cook 9 to 11 hours, stirring occasionally, until the mixture is thickened and dark brown. Uncover and continue cooking on low 1 hour.  Stir with a whisk, if desired, to increase smoothness. Spoon the mixture into sterile containers, cover, and refrigerate or freeze.

Makes 4 pints.