This app will help you improve your mental calculus. The mathematics you need to pass the consulting business cases.
It contains small exercises to do in your head which will make you progress in the math computations for the interviews.

I have created an (Android only at the moment) open-source app to practice the mathematics of the consulting interview. It has 7 downloads at the moment. The idea is to let the user press the answer of question such as percentages, percentage increases, multiplications, divisions and additions. We also accept feedback and contributions, and levels suggestions. I created the app especially to be able to rapidly implement new levels at the request of the user. Email me at [email protected] for any questions. I hope that you find the app useful.