In a large bowl, whisk together the flour, sugar, baking powder, baking soda, cinnamon, and salt.
In a separate bowl, mix the yogurt, milk, egg, and vanilla until smooth.
Pour the wet ingredients into the dry ingredients and gently stir until just combined.
Fold in the grated or diced apple. Do not overmix; a few lumps are fine.
Heat a non-stick skillet or griddle over medium heat and lightly grease it.
Scoop about 1/4 cup of batter per pancake onto the pan.
Cook for 2–3 minutes until bubbles form on the surface, then flip and cook another 1–2 minutes until golden.
Serve warm with your favorite toppings.