Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.
FCorp ID Book - ID Book is a handy, easy to use application specially designed to offer users a simple address book.
Open Contacts - Open Contacts is an advanced address book program for managing contact info of individuals and...
Truecaller - Find a person by a name or phone number worldwide for free using Truecaller.
FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts
ThisNumber - ThisNumber helps you find phone numbers for people and businesses!