Very easy to get proper rise and run for cutting your own treads!
The main drawback with this app is that all dimensions (whether feet or inches) have to be entered as "decimals", not as whole "feet" and "inches" with "sixteenths", "eights", or "quarters" . Consequently, this makes it cumbersome to use in the field where we use measuring tapes, I would not have purchased it had this been made clear in the app description.