Truecaller - Find a person by a name or phone number worldwide for free using Truecaller.
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.
Should I Answer? - See what phone numbers are most searched and find ratings and users reviews.
Open Contacts - Open Contacts is an advanced address book program for managing contact info of individuals and...
Phone.Report - Complete phone number report.
FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts