While Apple does have its own cloud service for email, contacts and calendars called MobileMe, it costs $99 per year and is not widely used. Gmail is a free service that offers email, contacts, calendars, tasks, documents and even more with Google Apps.
The benefit of MobileMe is the syncing compatibility with your iPhone, Mac, iPad and other Apple devices. With a little work though, you can have all your Apple computers and devices sync with a Gmail account.
To sync your Gmail contacts with your Mac computer, open the Address Book application, located in the dock and Applications folder.
Once open, click on Address Book in the menu bar and choose Preferences.
The Preferences window will open. Click on the Accounts tab in this window, located next to General.
Check the box next to Synchronize with Google located in the center of the window.
Click on the Configure… button to add your Gmail credentials. Enter your Google Account email address and Password then click OK.
Your Gmail contacts will populate your address book. Any changes made to the Address Book or Gmail will sync back and forth. You can also sync Yahoo contacts and of course, MobileMe with the Address Book as well.