Whisk together the dry ingredients: In a medium bowl, combine all-purpose flour, granulated sugar, baking powder, ground cinnamon, and salt. Stir until well mixed.

Mix wet ingredients: In a small bowl, whisk together the milk, egg, vanilla extract, and melted butter until smooth.

Combine mixtures: Gently fold the wet ingredients into the dry mixture, mixing just until combined.

Add apples: Fold in the diced Granny Smith apples, distributing them evenly throughout the batter.

Preheat air fryer: Set your air fryer to 370°F (188°C) and preheat for about 5 minutes.

Prepare the basket: Line the air fryer basket with parchment paper, brushing it lightly with cooking spray.

Scoop the batter: Use a spoon to drop approximately 3–4 spoonfuls of batter onto the parchment-lined basket.

Air fry fritters: Cook the fritters for 8–10 minutes, flipping them halfway through.

Make the glaze: In a small bowl, whisk together the powdered sugar, additional milk, and vanilla extract until smooth.

Cool and glaze: Allow fritters to cool slightly before drizzling or dipping them in the glaze.

Serve and enjoy! These delicious fritters are best enjoyed warm.