Wikipedia
Truecaller
Developed by True Software Scandinavia AB, "Truecaller" finds contact details globally given name or telephone number, and has an integrated caller ID service to achieve call-blocking functionality and social media integration to keep the phonebook up-to-date with pictures and birthdays. The client is available for Android, BlackBerry OS, iOS, Series 40, Symbian s60, Firefox OS, Tizen, BlackBerry 10 and Windows Phone.