Tapping on the "Email Captures" bubble on CircleBack app's home screen will display a list of the new contacts to review. If the contact is flagged as "NEW", then it is a contact that does not currently reside in your contact list. All other signature captures contain new information found for existing contacts.
If you wish to select multiple at once, press the "Select" button in the upper right corner. Following that, press on the contacts you wish to select. Once you have selected the contacts, you can press "Ignore" or "Save" at the bottom of the screen to take action on those contacts.
If you wish to review the captured signatures one at a time, press on a contact to review it. For existing contacts, the new information captured is highlighted and presented with information you already have for that contact.
Buttons at the bottom allow you to "Ignore" or "Save" the changes/new contact.