Smartr contacts - is a useful application which completes fast search of contacts you communicated with by means of messages, calls or e-mail even if those contacts are not included into your contact list
Contact hider is an important utility app which helps in hiding your selected contacts. It is very simple and easy to use. You can select the contact from the list and choose the one which you want to hide with a password
Google Apps Lookup (Android) - Lookup allows Google Apps for Business and Google Apps for Education users to find and contact any user in their corporate domain. Users can type or speak name, domain alias (e.g., jdoe) or email address, and Lookup will find the contact information for the user from the Global Address List and provide rich, structured contact data
NetQin Mobile Manager - NetQin Mobile Manager provides users with greater control over their communication needs. Customized auto replies & call blocking allow users to define who can and cannot communicate with them. Contacts backup ensures users’ contacts are never lost and can be transferred to a new smart-phone at the click of a mouse
Number Guru (Android) - The NumberGuru is the biggest, baddest, and most handsome callerID and reverse phone service you've ever seen. Find out instantly who's calling you.
Is it a spammer, is it a telemarketer or how about one of those pesky debt collectors? Maybe it's a long lost love or a job offer you've been waiting for