Blitzrechner +

A simple app to help you learn addition of numbers up to 20 with exciting statistics and a heatmap. The result sum doesn't exceed 23.

A student is offered a correct answer as well as a choice of answers similar to the correct one, so attention is required.
In case of a mistake, the question is put for a repetition in 3 and 10 steps after current.

No ads.
No IAP.
Works offline.