They sure can!
Add a Social Feed page for users to post updates, photos, and like and comment on others' posts.
Add an Announcements page for announcements.
Users will need to identify themselves to post to your app. In order to do so, when they are first trying to post they will be prompted to sign up or login to a Yapp account.
*We do not email your users or share your users’ contact information with anyone. This procedure is solely for users to use their real identities when posting to your app.