**Prepare the Batter:**
- In a mixing bowl, whisk together flour, sugar, baking powder, cinnamon, and salt.
- In another bowl, combine milk, egg, and vanilla extract. Gradually add the wet ingredients to the dry ingredients, mixing until smooth.
- Gently fold in the diced apples.
**Heat the Oil:**
- Pour vegetable oil into a frying pan or deep fryer, filling it about 2 inches deep. Heat the oil to 350°F (175°C).
**Fry the Fritter Bites:**
- Drop small spoonfuls of batter (about 1-2 tablespoons) into the hot oil. Fry in batches to avoid overcrowding.
- Cook for 2-3 minutes per side, or until golden brown and cooked through. Use a slotted spoon to remove the fritters and place them on paper towels to drain excess oil.
**Make the Glaze:**
- In a small saucepan, whisk together powdered sugar, milk, and vanilla extract until smooth. If the glaze is too thick, add a little more milk.
**Glaze the Fritters:**
- While the fritters are still warm, dip them into the glaze or drizzle the glaze over the top. Allow the glaze to set for a few minutes before serving.