Contact Activity is an advanced rule that allows you to give points based on contact's activity. This is an powerful concept that you can use create various campaigns for your reperks program.
How to use it?
In general, the most common way to use contact activity rule is to use it to create seasonal or product campaigns. For example, give additional 100 points when customer spent more than $200 during the month of August. For more, see campaigns you can setup with contact activity.