How to Turn off iCloud on iPhone
These instructions apply to devices with iOS 10.3 or higher:
How to Turn off iCloud on iPhone on iOS 10.2 or Earlier
The steps for turning off iCloud in iOS 10.2 or earlier are a bit different:
What iCloud Does When Turned On
The basic functions of the iCloud are pretty well known to most people: it’s used to keep data in sync across all devices that are signed in to the same iCloud account. That means that if you add a contact, update your calendar, or do any number of other things on your iPhone, that change will be automatically applied to your other iPhones, iPads, Macs, and other Apple devices. But iCloud does a lot more than that, too. You can also use it to back up data from your devices to the cloud, to use Find My iPhone to track lost or stolen devices, to upload photos to your public Photo Stream, and to share your Safari usernames and passwords across devices, among other things. Signing into iCloud also signs you into other Apple services and feature, like FaceTime, iMessage, Game Center, and Siri Shortcuts, too.
Why You Might Want to Turn off iCloud
Those all sound like pretty important features to use with your iPhone, right? They are, but you still might want to turn them off. For instance, you might not want to back up your iPhone data to iCloud or share your photos with the world. You might also want to prevent data from syncing from your iPhone to other devices. We don’t recommend turning off iCloud — it has too many useful features, most importantly Find My iPhone — but there are good reasons to do it in some cases.
How to Turn off Individual iCloud Features on iPhone
What if you don’t want to turn off all of iCloud, but just a few features? You can do that, too, by following these steps: