Filters in Real User Monitoring lets you dig deeper into the data or view more specific segments of your visitors and the performance based on Pages, Platforms, Browser, and the user location.
A quick filter can for example allow you to view data specific to Desktop visitors using Chrome from the United States:
The percentage of total visitors is shown in the top right corner and the most important data such as Active sessions, APDEX Score, Load Time and Bounce Rate are available at a glance. This allows you to easily find and tailor your report to the most important users of your website.
Page Groups are saved filters that allows you to use wild-card searches and monitor performance on a subset of your pages. You can manage them from the top right corner in the detailed report (they're also available if you share the report!)
A page group makes it easy to focus on the most important pages you have on your site, be it a checkout page, a signup page or maybe just your blog.
You can have up to 10 groups per Real User Monitoring site and it makes it a real breeze to just dig in to the most important pages and find any bottlenecks your users suffer.