Whisk whole-wheat flour, all-purpose flour, baking powder, baking soda, and brown sugar in a bowl.
Whisk egg, egg white and buttermilk in a large bowl. Stir in the dry ingredients, apples and bacon bits until just combined. (The batter will be thick.).
Brush a large non-stick skillet with 1/2 teaspoon oil and place over medium heat until hot. Cooking 4 at a time, use about 1/4 cup batter for each pancake and gently spread it to make them about 3 inches in diameter.
Cook until the edges are dry and bubbles begin to form, about 2 minutes. Flip the pancakes and cook until golden brown, 1 to 2 minutes more.
Repeat with the remaining oil and batter, reducing the heat as necessary to prevent burning. Enjoy!