Peel apple and dice fine into ~ 1/4 square cubes. Place in a small saucepan with 1-2 Tbsp. of water, cover, and heat over medium heat about 5 minutes or until apple has just softened. Remove from heat, drain if any water remains, and set aside to cool.
Crush shortbread cookies into crumbs. In a large mixing bowl, combine cookie crumbs, powdered sugar, cream cheese, 1/2 tsp. cinnamon, and melted white chocolate. Form into a ball as best you can, cover, and refrigerate for 1 hour.
Line a flat platter or baking sheet with wax paper. Remove truffle mixture from fridge and form into 12-14 balls, about 1 inch in diameter, placing them on wax paper. Return to the fridge for another 30 minutes to 1 hour of chilling.
In a small bowl, melt white chocolate in the microwave (30 second intervals tends to work well). Carefully dip each ball in the melted chocolate, rolling to cover the exterior and allowing excess chocolate to drip off. Place balls on wax paper. Sprinkle with cinnamon to finish.