This app is available on iOS and Android. Chromebooks that have access to the Google Play Store can access this app as well.
Pros: A very tactile game with intrinsic motivation and extensive addition/subtraction practice.
Cons: Sometimes it's more game than learning, and vigorous tapping can cause students to accidentally exchange resources.
Bottom Line: Hopelessly addictive addition/subtraction app keeps students learning and learning.
For students who need extra practice adding and subtracting large numbers, this app will help them.