Google Calendar - Spend less time managing your day & more time enjoying it
FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts
Jorte - Schedule books must be practical and has a good design.
Truecaller - Find a person by a name or phone number worldwide for free using Truecaller.
Business Calendar - Powerful and easy to use calendar app for Android including weather, widgets and tasks.
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.