Overview#Portable Contacts is an open protocol 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 proprietary contacts Application Programing Interfaces (API) such as Google's GData Contacts API, Yahoo's Address Book API, and Microsoft's Live Contacts API.
Portable Contacts combinesOpenSocial.
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: