Sum Them All 2.6

Brain needs to practice to keep its sharpness. Sum Them All let you do some daily brain practice by summing up digits.
There exist quite possibilities to train. In the settings you can set up number of digits to be shown, number of pages and time.
You can also work with negative numbers.
Find out your suitable settings. Practice daily and when these settings become easy for you try a little faster or more digits on one page.