Forms are complicated. There are many things you must take into consideration: binding an existing object (if any) to each sparate field of the form, validating them after user has submited the form, if invalid redisplaying it with POST data bound and with validation errors, binding the data back to an object...
Avris Forms add an abstraction layer that handles all of that. You just need to define the list of fields you need and their cofiguration options. You’ll get an object that will handle everything for you. Just handle it in the controller and display it in the view.