MacOS – Why is the “Synchronize with Google” option grayed out in Mountain Lion Contacts

Sure. On your iPhone, go into Settings > Mail, Contacts, Calendars, select Add Account... and add Google as Exchange (!!!) account. Using Google as Exchange account allows you to sync calendars and contacts.

See http://www.google.com/support/mobile/bin/answer.py?answer=138740&topic=14252

Now, gathering together all info spread around, into a checklist format:

• Google Sync is only supported on Apple iOS versions 3.0 and above, because that's when Microsoft Exchange was implemented and that's the protocol we will use.

• If your business, school, or organization uses Google Apps, your administrator will first need to enable Google Sync. If you're not, then there is no such setup - it's enabled by default.

• Double check you're using the correct gmail account - many users have more than one gmail, or google apps, with similar mails due to forwarding and often mistake this.

• Be sure to follow the steps mentioned above. Every configuration has to be done properly and it must lastly look something like this, from Mail, Contacts, Calendars > [your account] > Exchange Account [your email]:

When I had Snow Leopard I had the Google address book sync enabled and I somehow managed to put a 'sync' icon in the menu bar.

If I remember correctly I added it from the "old" iSync application (unsuccessfully trying to sync with a Samsung phone).

Now in Lion I still have it and it allows me to manually force the update of my Google address book, but I can't find how to obtain it as the iSync app seems to have disappeared.

This article here describes the situation of iSync in more details