The counting-up subtraction app lets students solve subtraction problems by counting up from the lesser number step by step. The first step is to get to the nearest multiple of 10. Then to the next higher 100 and so on until the greater number is reached. The count-up amounts are then added together to get the difference. Features: - The numbers can have up to 3 digits - You can set your own problems - The current operation for each column can be hidden - The operands for the current operation can be highlighted Other iDevBooks math apps iDevBooks math apps have been reviewed and endorsed by Wired.com, Common Sense Media, and other respected sites and organizations. Some of the over 30 other iDevBooks math apps are Visual Multiplication Table, Decimal Rounding, Whole Number Rounding, Column Subtraction, Column Addition, Long Division, Long Multiplication, Lattice Multiplication, Fraction Math, Partial Differences Subtraction, Partial Quotients Division, Partial Sums Addition, etc. Feedback and requests for new features New ideas to make this app better are welcome. Please visit idevbooks.com to give feedback. Privacy This app has no ads or in-app purchases and it does not transmit any data during the operation of the app. This app also does not contain any links to other apps or the web.