Preheat the oven to 350ºF (180ºC).
Line 12 regular muffin tins with paper liners or butter/spray the pans.
In a large bowl, mix the dry ingredients: 2 cups all-purpose flour, 2 teaspoons baking powder, ½ teaspoon salt, ¼ teaspoon ground cinnamon, ⅔ cup white granulated sugar and ⅓ cup light brown sugar. Mix to combine.
In a medium bowl, whisk 2 eggs, ¾ cup milk, ½ cup vegetable oil and ½ teaspoon vanilla extract. Do not beat, but mix well until no streaks of egg whites remain.
Add 1 teaspoon orange zest.
Add the wet ingredients at once to the bowl with the dry ingredients.
Mix until you barely have streaks of flour, but do NOT overmix. It will be lumpy and not completely mixed and that is fine.
Add ¾ cup blueberries and ¾ cup chopped apple, and mix lightly. Be careful not to mash the berries. Use a rubber spatula.
Divide evenly among the muffin cups or muffin liners.
Bake for 25 minutes, until the top is cracked, golden brown, and a cake tester or toothpick inserted in the center comes out clean. Don't overbake.
Let cool on a wire rack and eat warm or let cool down completely.
They are best eaten the day they are made, but you can keep them for a day at room temperature covered or wrapped.
Store leftovers, covered in plastic wrap or in an airtight container, in the refrigerator for a few days or frozen for a month.