"...if you want to create a meaningful design, the app makes it
easy. Creating a typical model begins with drawing walls. The wall
drawing tool snaps to 15 degree angle increments. The interface
displays the length of each segment as you draw it, and x- and
y-axis crosshairs appear to help you align parallel walls
precisely. And if you change your mind, you can move, transform, or
delete walls at any time."