Counting the total purchase price is much faster and easier with the use of this application than using a regular calculator. When this app is useful? - If you want to use a voucher at the store and your total price cannot be less than some value. - You cannot exceed a certain amount because you do not carry more money. - You want to make sure that the prices off the shelves correspond to the prices on the receipt. - You are using promotions such as "10% bonus for purchases worth $50, $100, $15