Peel the apples and cut into fairly thin (about ¼-inch-thick) slices.
Combine the apples and juice in a medium skillet. Cover and steam, stirring occasionally, until they've softened but still hold their shape, about 4 minutes.
Add the berries, maple syrup, and cinnamon, and cook until the the berries have started to burst and the apples are just tender, about 3 to 4 minutes longer.
In a small container, combine the arrowroot or cornstarch with just enough cold water to dissolve smoothly, and stir into the skillet. Cook briefly, just until the liquid in the skillet is thickened, then remove from the heat.
Sprinkle the granola evenly over the surface of the fruit. Allow the crumble to cool in the pan for a few minutes, then serve in small bowls. If desired, top each serving with a dollop of nondairy ice cream.