Mavention Popular Documents is a free App for SharePoint that shows documents popular around you. Using Office Graph Mavention Popular Documents finds documents relevant for you and your work.
To keep you productive and away from opening the same documents over and over again, Mavention Popular Documents uses information from Office Graph to keep track of which documents you have already seen. Those documents are displayed greyed out so that you can easily distinguish them from other documents that you haven't seen yet.
The information about which documents you have seen is personal and can be seen only by you. It is stored in Office Graph from where only you can retrieve it.