Google Tag Manager
For upgraded GroovyCart shops Google Tag Manager is fully integrated. This gives you control over how your shop works and performs with an easy to use Google interface.
Google allow you to add marketing and analytic tags without having to edit any code, all you need to do is sign up for a Google Tag Manager account and start picking what tags you want to use.
You can even set up complex rules that allow you to pick what is displayed on each page.