If you click on the diagram in the upper left corner a page is opened where you can compare your own measurements with each other.
When you arrive the last 10 measurements are shown in the graph. With the help of the dropdown menus you can choose to compare speeds in between your different rooms or between measurements made over wi-fi or a mobile connection. This helps you in drawing conclusions based on previous measurements. One example could be checking at what time during the day my wi-fi is fastest in my bedroom.