Easy to use, and very accurate.

I have this and the iOS version, and love them both. You can quickly search for addresses and phone numbers for businesses, and add results to your Contacts list with the click of a button.
Its fantastic, because this means all relevant data is added directly, and if you have iCloud Contacts synching enabled, this means your iPhone/iPad will be immediately updated with the new contact entry.

doggrowl about Yellow Pages