Portable Contacts

Portable Contacts is an for developers to make it easier for developers to give their users a secure way to access the address books and friends lists they have built up all over the web. The goal of the project is to increase data portability by creating a common and open specification to bridge contacts Application programming interfaces (API) such as Google's GData Contacts API, Yahoo's Address Book API, and Microsoft's Live Contacts API. It combines OAuth, XRDS-Simple and a wire-format based on vCard harmonized with schema from OpenSocial.

The editor of Portable Contacts specification was Joseph Smarr of Plaxo and the project co-maintained by Chris Messina.

Portable Contacts is used by services such as Google Contacts,Windows Live Messenger Connect, as well as other specification such as OStatus.

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