FlexForm is an enhanced HTML5 Form rendering engine.
It renders HTML5 form elements and allows editing or creating one or more pages with one form.
When you are familiar with creating HTML5 forms you will have no problem using FlexForm.
To get started for the first time, have a look at the get started documentation.
All documentation can be found here.
This version 1 is a complete rewrite and stripped down version from the previous WSForm.