Google Calendar works with a number of desktop applications and mobile devices including iCal, iPhone and iPad, Blackberry, Android, Nokia/Symbian, and Windows Mobile phones.
"Google Calendar Sync now supports Outlook 201032-bit. To start syncing your calendar with Outlook 2010, download Google Calendar Sync version 0.9.3.6. Once you install it, a Settings window will appear. Enter your account's email address and password, choose your sync option and sync frequency, and you're done! (Note: If you're already using Google Calendar Sync, you'll still need to download and install this new version in order to be able to sync with Outlook 2010," informs Google.