Qlik Sense Workbench is a development toolbox used for building solutions with Qlik Sense. It includes JavaScript API libraries used for building Qlik Sense visualizations or for building mashup websites with Qlik Sense content.
Qlik Sense Workbench provides developers with a quick start for creating custom visualizations and mashup websites, including code samples and templates for creating different types of visualizations as well as templates for creating basic mashup websites. Those templates constitute in fact the perfect starting point for your next mashup project.
Qlik Sense Workbench provides three JavaScript APIs for building extensions and mashups. The Extensions API for building visualizations, the Mashups API for building mashups websites, and the Backend API for communicating with the Qlik Sense engine.
How can I access to Workbench?
The good news is Workbench doesn't have a separate installation package, so if you already have Qlik Sense Server or Desktop you have Workbench working.
To launch Qlik Sense Workbench open a web browser and type in the URL https://ServerName/workbench/ . If you are a Qlik Sense Desktop user, make sure it is running and do the following, open a web browser and type in the URL http://localhost:4848/workbench/et voila!
How does Workbench work?
To reply to that question I leave you with a 5 min video that will walk you through the mashup creation process.
Enjoy!
AMZ
PS: Remember you can find lots of useful videos, howtos and tutorials at the Qlik Youtube channel