Some parts are quite good

I have bought this app to have this kind of fun always with me. During business trips and so. It is not bad and you can test your brain easily. But it is not as good as I thought. It will not be enough to replace the book Secrets of mental math from Arthur Benjamin and Michael Shermer. But for some training it is okay. It is easy to work with! For everybody as a start it is good. For more you need ... more!

Der Sandmann about Mathemagics: Mental Math, v4.2