FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts

Garden - Container Engine

Truecaller - Find a person by a name or phone number worldwide for free using Truecaller.

Affinity - Relationship Intelligence, Reimagined

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.

Followup.cc - FollowUp for email is a lightweight productivity suite that keeps your conversations and tasks from slipping through the cracks. Set perfectly timed reminders that arrive at the top of your inbox, right when you need them.