Really great app. The ONLY reason I didn't rate it five stars is because it does not have an iOS counterpart. If there were an iOS version of this app, it would be PERFECT!!What I like most was something that I wasn't even looking for: The ability to protect your contacts in a strongly encrypted database. An additional nice features is the ability to create multiple different address books and have different categories and different layouts in each address book. This is a serious bonus for when you use your address book for more than just business and personal contacts (like tracking all of your email address aliases).Best $8 I've spent in a long time. The app is not cheap, but it is worth it. It may not be the most sophisticated address book program available, but it is the only one I've found that operates separate from Contacts that more than meets the needs of an address book.Why this app? I was looking for an address book that freed me from the Mac OS Contacts app and its now forced integration of address completion in all apps. It used to be that you could disable autocomplete in Mail, but you no longer can (as of Mail 7.x). Thus, I found this app and it is worth every penny I paid for it. Just simply import all of your Contacts into Private Contacts, archive your Mac OS X Contacts by exporting them (in case you ever want to use the Contacts app again), then delete the Mac OS X Contacts' cards, and no longer are you forced to have to deal with address autocomplete in Mail, Messages, Facetime, etc. (Note: I had some custom fields in Contacts, and those had to be manually updated in Private Contacts, but this was not a major issue.) This is simply the easiest way -- actually, the only way -- I have found to disable address autocomplete in Mac OS X.Now, just give me an iOS app that integrates with Private Contacts, and I'll be very happy!