Menu bar version allows you to search, contact (email, iMessage, call), add new contacts, view contact details, edit contacts (will open a new window), add a contact to favorites, merge or delete contacts.
To search a contact, start typing in the search bar; search doesn't work in URL fields yet. FullContact will automatically show details for the first contact in the list.
To add a new contact, you will need to type in information that's not matching any existing contact, or by clicking ⌘+ N (this will open dock version).
To edit a contact, click on the pencil icon in contact view or with right-click on a contact. Right-click also allows you to email, iMessage, call a contact, add it to favorites, share, or delete it.
You can also multi-select contacts to merge them, contact them (email, iMessage, call), favorite, share, or delete them.