Peel, core, and dice your apples into small, uniform ¼-inch cubes. If your apples seem particularly juicy, gently pat them dry with a paper towel.
In a large bowl, whisk together the flour, sugar, baking powder, salt, cinnamon, and nutmeg until thoroughly combined.
In a separate bowl, beat the eggs lightly, then add milk, melted butter, and vanilla extract. Whisk until smooth and fully incorporated.
Pour the wet mixture into the dry ingredients and stir just until combined – about 12-15 strokes with your spatula. Gently fold in the diced apples until they're evenly distributed throughout the batter.
Preheat your air fryer to 350°F (175°C) for 3-5 minutes. Lightly spray the basket with cooking spray.
Using a cookie scoop or tablespoon, drop rounded tablespoons of batter into the air fryer basket, leaving about 1 inch between each for expansion. Avoid overcrowding – typically 6-8 fritters per batch. Lightly spray the tops with cooking spray for extra crispiness.
Air fry for 8-10 minutes or until the fritters are golden brown and a toothpick inserted comes out clean. Check at the 7-minute mark for your perfect level of golden crispness.
While the fritters cook, mix the powdered sugar, milk, vanilla extract, and salt in a small bowl until smooth and pourable. Adjust consistency with additional milk or powdered sugar as needed.
Transfer the cooked fritter bites to a cooling rack and drizzle or dip them in the glaze while still warm.