APT is three calculators in one. First, a product pricing calculator. APT allows you to build up the cost of producing or buying your product wholesale, add in different types of expense including fixed expense per unit sold, expenses variable with the product cost and expenses variable with retail price. Add in profit margin and sales distribution / retail mark up costs and out comes a price. Easily see the effect of adding or subtracting out product components, changing retailer load or profit levels, or adjusting expense levels.a normal everyday calculator with all the functions you expect. Second is a loan/annuity/bond calculator that lets you solve for any component (initial balance, term, interest rate and ending balance). Last, a regular calculator for every day use. All of these for free without annoying pop up ads. Try it now!