The Main Overview page provides a summary of all of your assets/devices on one page. The map will show you where all of your devices are located. You can also see how many of your devices are in Failover alarm states of active vs. inactive as well as how many of your devices are in connected vs. disconnected WWAN alarm state, shown as pie charts on the bottom left.
By default this view, and all views are filtered for the past 7 days. This can be changed using the Date Filter across the top left. There are buttons underneath these pie charts that allow you to see a filtered asset listed of devices based on these alarm states.