Funambol - Funambol is the leading provider of platforms that power many cloud services.

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.

ownCloud - ownCloud is an open source project enabling businesses to host their own cloud storage while maintaining regulatory and compliance needs.

Open Contacts - Open Contacts is an advanced address book program for managing contact info of individuals and...

fruux - Free service that takes care of your contacts, calendars and more so you don't have to.

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