Preheat the oven to 350ºF.
Add the apples and 1 teaspoon oil to a saucepan over medium-low heat. Cook until softened. Stir in ½ teaspoon cinnamon, the ginger and 1 tablespoon honey.
Meanwhile, make the oat topping: In a bowl, mix together the oats, flour, pinch of cinnamon, 1 tablespoon oil and 1 tablespoon honey. Crumble it together with your fingers until achieves a breadcrumb-like consistency. Add extra sweetener or oil if you like a chunkier texture.
When the apples are golden and start to caramelize, transfer to an oven-safe baking dish. Scatter the blueberries on top. Spread marmalade over the top of the fruit. Crumble oat topping over it in an even layer.
Bake for 15-20 minutes, until golden, crisp and the blueberries are bubbling. Serve with coconut yogurt or non-dairy ice cream.
