it helps you generate a lot more than just tags. From the documentation:
You feed them with a form field, and they display the corresponding HTML form control, with a populated value, constraints and errors
and
A rendered field does not only consist of an tag, but may also need a and a bunch of other tags used by your CSS framework to decorate the field.
(http://www.playframework.com/documentation/2.2.x/JavaFormHelpers)
So instead of
<label for=...>
... error mesages
<input ...
</label>
you have just one readable line
@inputText(accountForm("id"))
EDIT: It will also read constraints on your java beans, e.g
@Constraints.Required
@Constraints.MinLength(5)
public String firstName;
and use html5 browser validations and display the coinstraints to the user. (http://www.playframework.com/documentation/2.2.x/JavaForms)