I found this app for my iphone and ipad, and it's free!
It's free for android phones as well.
It is a quilt calculator.
It tells you:
Backing and Batting
Pieces to Yardage Area
Set-in and Corner Triangle
I always use the "binding" calculator when I make a quilt.
I cut my binding 2" wide and this app tells me how much yardage I need to buy for the binding and how many strips I need to cut.