The Ten Key Calculator operates in a manner similar to desktop adding machines. Ten Key adds numbers and leaves a list that can be modified by inserting, deleting or modifying entries. It allows a preference of left or right hand keyboards when in landscape mode. Setting the decimal place preference to + will automatically insert a decimal point in the cents position. The size of the font for each area of the main screen can be adjusted for maximum readability for your device. The file screen allows you to save, open, append, rename or delete your work. While it is simple to use it does not operate exactly like a hand held calculator. If you are not familiar with how a ten key machine operates there are help pages included to help you become acquainted with its operation. There are help pages for each of the screens (main, file, preference and help), each of the controls (edit and font) as well as an overview and introduction to Ten Key included with the application. Please visit our website for more information, including help pages that are similar to those included with the Ten Key Calculator. Thank-you for considering our product!