All duplicate contacts are checked and you can choose the delete option to remove them (In the FREE version you can only delete a maximum of 90 contacts at one time).
This contacts app also comes with a backup utility. This way you can restore any deleted contacts if needed. The backup option can also be used to restore contacts anytime in the future if the need arises.
Apart from finding & deleting your duplicate contacts you can also do the following with Duplicates View & Destroy:
* There is a dialer that allows you to make calls to contacts
* Do a text-based search on all contacts
* Add new contacts
* Edit existing contacts
Note that with the FREE version you can ONLY DELETE 200 duplicate contacts at one time (you can view unlimited duplicate contacts). With the pro version, there is no limit on a number of contacts you can delete at a time.