Google Contacts Data API

[engine]

The Google Contacts Data API allows you to own your own contact data. We expect the API to be useful for a big range of applications. For example, developers can use it to:

Import a user's Google contacts into their web or desktop application

Export their application's contact list to Google

Write sync applications for mobile devices or popular, desktop-based contact management applications

Google Contacts Data API [googledataapis.blogspot.com]