First version
Brain training with mathematic operations.
The principle is very simple: on the one hand the app proposes a target number, and on the other hand it gives you some operation symbols together with a collection of digits. Then you have to reconstruct the operation to get the number. This is a very good mathematical brain training.
This exercise is excellent for training mental computations. Doing that is a very good practice for mathematics, in particular for all the arithmetic operations: addition, multiplication, division and subtraction. The objective is to make you confortable with number manipulation.
There are several levels. The first ones are very easy, ideal if you are learning to count. And step by step, it introduces more and more difficulties. The brain training is progressive.