Here is the context:
This chapter covers
Generating HTML with UI component tags
Building forms and beyond
Snazzing it up with templates and themes
Surveying the components
It means the author wanted to talk about building forms plus some other stuff that is related, but is either (a) less important and so shouldn't be mentioned in the sub-heading, or (b) involves several different topics that cannot easily be summarized in one or two words.
Building forms and beyond
means "Building forms and more things you can do related to building forms".
In this context it means "to go further than the subject matter or title suggests".
Building a web form requires that you do ABC, but having learnt those skills you could employ them to do XYZ which has nothing to do with building web forms.