My Mental Arithmetic Lite

The application was designed for my kid to train the ability of mental arithmetic in 2-4 elementary school classes.
Sure adults could have a try to train their brains as well. I am sure you will be astonished comparing your first results and results you gain after one month of training.

The following features are included into this application:
- summarize up to 50 (or 1000 full version)
- subtraction up to 50 (or 1000 full version)
- multiplication up to 10 (or 20 full version)
- dividing up to 10 (or 20 full version)
- dividing with a rest (full version only)
- combination of these samples in one exercise (full version only)
- shuffle the unknown value place (full version only), e.g. the first summand is unknown: ??? + 2 = 5

I hope you will enjoy trying the "Lite" version.
Any feedback to improve the usability, quality and features is welcome.