Combine all ingredients in a shallow dish or saucer.
For the wet rim:
Wet the rim of a martini glass or tumbler with the slice of apple, reserve for garnish. Dip the rim of the glass in the sugar mixture and reserve.
In a cocktail shaker, pour the cinnamon schnapps, vodka, and ginger ale over ice, shake and strain into the glass. Garnish with the apple slice. .