Add the sliced apple, water, 1/8 teaspoon cinnamon, brown sugar substitute, and a tiny pinch of salt to a small skillet over medium heat. Cook for 3–5 minutes, stirring occasionally, until the apples soften and become lightly caramelized.
While the apples cook, toast the low-carb bread until golden and crisp.
Spread the light cream cheese evenly over the toast. Spoon the warm cinnamon apples over the top.
Sprinkle with the remaining cinnamon and drizzle with a little sugar-free caramel sauce and crushed graham crackers, if desired.