iCloud stores your calendar, contacts and mail, and automatically pushes them to all your devices. So you can switch from one device to another and still go about business as usual.
Make or change an appointment.
It appears on all your devices.
Calendar
A calendar that keeps up with you.
Update your schedule in one place and see your changes everywhere. When you have multiple devices, iCloud updates them with your most recent appointments — saving you time for all the other things you have going on. You can also share calendars with other iCloud users. A diary your whole family can add to. Or a team schedule that every player can access. As soon as someone adds or edits an event, iCloud updates it wirelessly on everyone’s devices.
Mail that delivers. Free.
When you set up iCloud, you get a free iCloud.com email account. iCloud automatically pushes new email messages to all your devices, so your inbox and folders are up to date everywhere you check them.
Now no matter which email account you’re using, iCloud works with the Mail app on OS X Mountain Lion and on your iOS devices to keep your recent email address history up to date, so you won’t have to look up any addresses you’ve used before. Set up a VIP list so you’ll never miss an important message from your boss or your BFF — no matter which device you’re using.
Contacts
Make connections everywhere you go.
With iCloud, your entire address book is on whichever device you’re using, any time you need it. Say you add someone to Contacts on your iPhone, iPad or iPod touch. iCloud automatically pushes the new contact to Contacts or Address Book on your Mac, or to Outlook on your PC. So you don’t have to connect your device to your computer to keep track of all those names and faces.
Bookmarks, Notes, Reminders
Always up to date. Always with you.
iCloud stores the web pages you’ve bookmarked, notes you’ve written and reminders you’ve created. It’s all there, everywhere you go. So when it comes to your devices, you can switch things up without mixing things up.
iCloud.com
Your place on the web.
iCloud works great with popular applications including Mail and Calendar or iCal on a Mac and Microsoft Outlook on a PC. But if you happen to be away from home without your computer or one of your iOS devices, you can access Mail, Contacts, Calendar, Notes, Reminders, Find My iPhone and iWork Documents — ad-free — from any computer at iCloud.com.