Starting in version 1.15.0 of Greek Chapter, users with the owner, admin, or announcement admin permission within an organization are able to see who has viewed an announcement and how many times.
From the mobile app:
Tap on an announcement either from the Dashboard or the Announcements page (more tab, announcements button)
Tap the gear icon in the top right
Tap Announcement Views
All organization members and how many times they have viewed the announcement are visible
From the web app:
Navigate to the announcement details page for an announcement. This can be done by clicking a dashboard announcement card (not the edit pencil)
Next to the announcement title, click the eye icon
You are now on the announcement view page