Preheat oven to 350°F (175°C). Grease a loaf pan.
In a mixing bowl, combine grated zucchini and apple.
In another bowl, mix flour, sugar, baking soda, cinnamon, and salt.
Add eggs, oil, and vanilla to the zucchini and apple mixture. Stir well.
Gradually add the dry ingredients to the wet mixture. Stir until just combined.
Pour batter into the prepared loaf pan.
Bake for 60 minutes or until a toothpick inserted into the center comes out clean.
Let cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.