First announced back at WWDC in June, iCloud replaces MobileMe, and brings a host of new functionality with it.
Not only will you be able to store your data online and find or remotely disable a missing handset, iCloud will allow you to keep data on all your iOS and Mac devices nicely synced up, including contacts and documents.
What's more, it offers Photo Stream – this sees pictures synced and shared using push technology; so if you take a picture on your iPhone, it will be uploaded to iCloud automatically so you can access it on any other device.
Apple's iCloud UK pricing is based in tiers; a basic package won't cost you a penny and gives you 5GB of online storage.
For an additional 10GB you'll pay £14 a year, 20GB extra is £28 a year while 50GB of extra space will be £70 per annum.
Also announced today: the iPhone 4S, Apple's incremental update to the iPhone 4.