Google has just released a beta of their latest mobile service — Google Sync. This service makes it possible to sync your Google Calendar with your iPhone, Windows Mobile or other SyncML client, for free!

They use the Microsoft ActiveSync protocol, meaning that support is already built-in. To enable this on your phone right now, go to the Google Sync website and follow the straight-forward instructions. Be sure to backup your calendars and contacts beforehand though, since all information will be erased on your phone.

The easiest way to manage the contacts is to enable syncing them to Google using iTunes. Instructions for this are available as a part of the setup process on the site, so there is no need to worry.

The above mentioned process will enable synchronization of the default calendar only! If you want to access multiple calendars, or even imported calendars which are owned by others, you need to go to m.google.com/sync using your phone as the Google help pages suggest.

There is a problem however, this does not work with Google Apps domains. To sync multiple calendars with a Google Apps domain, first make sure that you are using the “English” language on the website. There is a link to switch if you don’t.

Second, don’t go to the page mentioned in the help section, but instead go to m.google.com and choose “Sign in with your Google Apps” link. When you have signed in, there will be a sync icon presented, which will take you to your calendar sync settings. From there you can add multiple calendars, which will then automatically be synced to your phone.

One downside of using Google Contacts instead of the local Address Book is that the photos aren’t synced properly. There is however an application available for Windows with no name that syncs the photos from Facebook to your Google Contacts account. While this might not be the best option, it definitely beats not having any pictures at all.