For many years, we've supported two open protocols for accessing Gmail and Calendar from mobile appsand devices: IMAP for email and CalDAV for calendar. These protocols, combined with the options toaccess Gmail, Calendar, and Contacts with your desktop or mobile browser and via native apps on iOS andAndroid, help ensure you have a great experience regardless of the device you use.Starting today, we're adding CardDAV - an open protocol for contacts - to that list. CardDAV enables 3rdparty clients, like the iOS contacts app, to sync your Google contacts. By supporting IMAP, CalDAV, andCardDAV together, we’re making it possible for 3rd parties to build a seamless Google Account syncexperience. (http://gmailblog.blogspot.nl/2012/09/a-new-way-to-sync-google-contacts.html)