I would use this along with math drill apps during centers for math practice. It's an excellent app that kids won't get bored of over the school year.
I am reviewing this, because kids love this app. They mostly like it, because they have to move the marble around by moving around the iPad. It is interactive like Sushi Monsters. The app is more involving than rote memory of number skills, because kids have to calculate in their head among a few numbers and pick two.