Sale Price by TerraMar is an easy to use app which calculates an items sale price. Simply enter the items Retail Price and use the Markdown controls to set the First and Second Markdown percentages and the application does the rest.
Once Markdown percentages are set, they will remain until changed by the user. That way you wont be slowed down during a great sale. For smaller screen sizes, the numeric keypad can be hidden by simply tapping the Retail Price field.