Google Calendar - Spend less time managing your day & more time enjoying it
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.
CalenGoo - Features | 1.0.175 for Android™
Apple Contacts App - Access and edit your contacts from personal, business, and other accounts with the Contacts app.
Jorte - Schedule books must be practical and has a good design.
Windows Contacts - Windows has many extraordinary organizers, and in the event that you include distributed storage, then you presumably have more.