Saturday, January 19, 2013

CardDAV, or how to get iCloud contacts on Android

For years, the fine folks at have been making calendar sharing and synchronization easier for everyone, based on a derivative of the WebDAV specification called CalDAV. But it's only been a few months since Google—one of the leaders in standards-based calendar sharing—has jumped on to the second Calconnect bandwagon: contact card sharing using the CardDAV specification.

Those who remember early card sharing will recall vCard, the Microsoft-centric way of sharing contact information. CardDAV provides a consistent standard for two-way synchronization, with a push model that keeps everything in sync on a real-time basis.

Real-time synchronization was lacking in meta-sync programs like Apple's Address Book app ( for those of you on a Mac OS X machine, renamed for the iOS crowd) and even some of the more popular and expensive synchronization tools (SyncMate, anyone?).

The problem with synchronizing with an application, rather than at an operating system level, is that the applications must all be open and connected to the interwebs at all times. Otherwise, changes to a contact on two offline devices resulted in synchronization nightmare, and changes on one online and one offline device in the same time period added an even more complex synch issue.

It's no wonder the late Steve Jobs famously said, of and MobileMe, that Apple hadn't done it right. Once Apple decided to do it right, they embraced CalDAV and CardDAV, and iCloud was born as a central repository for all things synchronized. While iCloud still has its growing pains, Apple's move to CardDAV in particular pushed Google to figure out how to integrate with Apple as tightly as the search giant had integrated with Microsoft.

Microsoft's version of both calendar and contact sync, for real-time updates, is Exchange, and Google licenses EAS for use in Google Apps for Your Domain (which was free, at least until the end of 2012). EAS is also found in iOS devices, at least for paid email accounts that support Exchange.

For mere mortals, though, the Google move to CardDAV opens the way to have your iCloud contacts on both an iOS device as well as an Android device. It isn't seamless but it's a good start.

Given the recent support by Google, it's certain we'll see integration of CalDAV at the operating system level for Android OS at some point in the future. For now, consider using the free or paid beta versions of Marten Gajda's CardDAV-Sync (and even his more mature CalDAV-sync).

If you use CardDAV-Sync, remember you'll need three important pieces of information: server URL, username and password.

We'll supply the first one for you here, if you're synching your iCloud contacts down to an Android device: type in the Server name field.

We also suggest you enable SSL, needed for the https secure server noted above, and—for the time being—keep the one-way synchronization turned on so as not to mess up your iCloud contacts while Marten gets the kinks worked out. It's the check-box option after you enter your iCloud username and password, just before you name the newly created sync within CardDAV-Sync.

Happy real-time synching!

No comments: