Subtraction Math Trainer is a math learning app designed to help you to practice subtraction. The built-in handwriting recognition allows you to draw answers directly on the screen. Choose between six different ranges: 1 to 10. 1 to 20. 1 to 50. 1 to 100. 1 to 200. 1 to 1000. Choose between four task modes: 3-2=? 3-? =1? -2=1? -? =?