DataLayer is a variable used to transfer data from a website to the Google Tag Manager container. Data that the page passes to DataLayer can be used to create variables, rules, and tags. We will help you implement DataLayer on your website or prepare documentation for your developers how to properly implement the data layer. Alternatively, if you have already implemented DataLayer in accordance with the Google Analytics specification, we will adapt it to the operate the Google Analytics 4 (GA4) so that all data is collected correctly.