Alerts can be configured to "trigger" when any metric changes. The limit can be set as an upper or lower limit (less than/more than X), an absolute change up or down (increases/decreases by more than X), or a percentage change up or down over a chosen time period. Once that configuration is "triggered" the user can receive an alert by email, text, push notifications or any of the other actions available with Dashboard of Things
To create an email alert, click on the settings of the dashboard app for which you would like to create an alert. In the menu, click "Potion"