iCloud Explained

For iOS 17, macOS Sonoma

Intro

If you have multiple Apple devices, you may know that there are many features that allow them to integrate with each other to keep content up-to-date across all of them. In this guide, I will give an overview of how iCloud, the service that facilitates this interconnection, can help you manage and sync your content, as well as how it can help protect your privacy and security. The good thing about it is once you have a few things set up, features largely work automatically with very little additional interaction required from you, the user.

Terminology

iCloud is the Apple service that allows Macs and iOS devices to keep content in sync between them. By default, you get 5GB of free storage space, upgradable up to 12TB, to store data such as documents, photos, emails, contacts, calendars, and more. With any paid storage plan, you get several additional features marketed collectively as iCloud+.

“The cloud” refers to the nebulous network or “cloud” of servers that provides the backend infrastructure for syncing and storing data on the Internet, and is not an Apple specific term. Popular cloud services from other companies include DropBox, Google Drive, OneDrive, and others. The use of these and similar services is referred to as “Cloud computing.”

Setup

Like other Apple services, iCloud requires an Apple ID. If you’ve used other Apple services such as the iTunes Store or AppStore, you already have an Apple ID. If you haven’t, you can create one for free.

When you first set up your Mac or iOS device, you were probably asked to sign in with an Apple ID and password. If you entered this information during setup, iCloud is probably set up already. If you didn't, you'll be presented with an option in Settings on iOS and iPadOS and System Settings on macOS to do so.

iCloud features

Once you've signed in with your Apple ID, specific iCloud features can be configured in Settings (System Settings on macOS) > [your name] > iCloud. In this section, I will give an overview of several of these features.

Mail allows you to create a free @icloud.com email address that you can use with the Mail app on macOS, iOS, iPadOS, other email clients, and on the web. In addition, with iCloud+, if you have control of another domain, you can associate it with your iCloud account to use custom email addresses in addition to, or in place of, your @icloud.com one. For more information about using custom domains with iCloud Mail, check out the Apple Support article “Use Custom Email Domain with iCloud Mail.”

If apps like contacts, calendars, and reminders are listed and enabled, those apps are using iCloud to store and sync data across devices. For example, if you add a contact to the Contacts app on your iPhone, it should automatically appear in the Contacts app on your Mac. Likewise if you add an event in the Calendar app on your Mac, it should automatically appear in the Calendar app on your iPhone, or whatever other devices you have signed into your Apple ID. Make sure these apps and services are enabled on all the devices you want to sync them on.

More detailed descriptions of some other iCloud features are given below:

iCloud Drive

iCloud Drive allows you to store files that are kept up-to-date on all your devices. It can be accessed through the Files app on iOS and iPadOS, or via Finder on macOS by choosing Go > iCloud Drive, or pressing Command-Shift-I.

It opens like a typical folder, where you can add, modify, and delete files as you would any other folder. Any changes you make on one device should then sync to iCloud Drive on your other devices.

On macOS, the contents of your desktop and documents folder can be stored and synced using iCloud Drive, useful if you, for example, have multiple Macs and want to mirror the contents of your desktop and documents folder on all of them. In addition, enabling the “Optimize Mac storage” toggle will cause your Mac to only retain recent iCloud Drive data locally. While the entire contents of iCloud Drive is displayed when you open the folder, only recent files are actually located on the Mac’s internal storage; other files will be downloaded as you open them.

iCloud backup

iCloud backup, (iOS and iPadOS only) allows you to store a full backup of your device in iCloud, so if you ever lose your data or need to replace your device, you can sign into your Apple ID and download the data on the new one. By default, backups happen daily when your device is connected to power, locked, and connected to Wi-Fi, and can be manually initiated in iCloud Settings. In addition, if your wireless carrier supports it, you can enable the “Backup over cellular” toggle to allow backups over your device’s cellular connection.

Tip: After replacing an iOS or iPadOS device and restoring from an iCloud backup, the backup of the old device is retained in addition to that of the new one, unnecessarily occupying valuable space in your iCloud account. When you’re confident that all your data has been restored, you should delete the backup for the old device by going to Settings > [your name] > iCloud > iCloud Backup, double-tapping the name of your old device, and then double-tapping “Turn off and delete from iCloud.”

Messages in iCloud

Messages in iCloud allows you to sync your existing iMessages and text messages between your devices. With messages in iCloud disabled, new messages are pushed to your devices, but they must be manually deleted from each device. In addition, current messages aren’t synced when you sign in on a new device.

To enable this feature on iOS and iPadOS, double-tap the “Show all” button in iCloud settings, double-tap “Messages,” and enable the “Sync this iPhone” toggle. To enable this feature on macOS, open Messages and choose Messages > Settings, (or press Command-Comma) click the iMessage button in the toolbar, and select the “Enable messages in iCloud” checkbox.

Find My

Find my allows you to view the locations of your signed in devices on a visual map, play a sound on a lost device, and lock or wipe a lost device's contents. In addition, you can use Find My with AirTag and other supported accessories to help locate commonly misplaced items such as keys, wallets and bags.

You can check if Find My is enabled on an iOS or iPadOS device by going to Settings > [your name] > Find My, and making sure the “Find My” toggle is on. You can check the same setting on a Mac by clicking the “Show all” button in iCloud settings, and making sure “Find My Mac” is on.

Devices and accessories can be located in the Find My app on iOS, iPadOS and macOS, as well as Siri on iOS, iPadOS, macOS, watchOS, tvOS, and HomePod. Activating “Lost mode” on a lost device allows you to display a phone number on that device for someone to contact you should they find it. Likewise, activating lost mode on an AirTag allows you to provide a phone number that anyone with an NFC capable smartphone can view by tapping their phone against the AirTag. If you erase a device, it can no-longer be tracked, and your Apple ID and password will be required to reactivate it.

Like iCloud backup, Find My may retain your old devices and accessories, which may be confusing when you’re trying to figure out what device or accessory is what. This can happen particularly on devices and accessories you never signed out of. Therefore, you should remove your old devices and accessories so as not to confuse them with your current ones. To do this, go to Settings (System Settings on macOS) > [your name] and select your old device or accessory, followed by the “Remove from account” button.

iCloud keychain

iCloud keychain allows you to sync your login credentials and credit cards across devices. When you choose, for example, to save a username and password in Safari, that information is stored in a location on your device called a keychain, where it can be used to autofill webforms in the future. With iCloud keychain, your saved credentials are synced to all your devices for autofill.

In addition, when creating an account for a website or app, iCloud keychain can automatically generate a random, secure password that is stored and synced in iCloud and can be autofilled on your signed in devices. Saved login credentials can be accessed and managed in Settings (System Settings on macOS) > Passwords. Saved credit cards can be accessed and managed in iOS and iPadOS by going to Settings > Safari > autofill > saved credit cards, and within Safari on macOS by choosing Safari > Settings, (or pressing Command-Comma) clicking the autofill button in the toolbar, and clicking the “Edit credit cards” button.

Hide My Email

Hide My Email (iCloud+ only) allows you to generate random email addresses that forward to your real email address. This can be useful if you, for example, sign up for a service that requires an email address, but don’t want to give it your real one.

Random email addresses can be generated and managed in the Mail app on iOS, iPadOS, and macOS, as well as iCloud Settings on both platforms. Similar to Sign in with Apple, email addresses can be deleted at any time, preventing an individual or service that’s abusing it from communicating with you.

iCloud Private Relay

iCloud Private Relay (iCloud+ only) helps protects your web browsing privacy by sending your requests through several internet relays, masking your true identity.

Normally, when you access a website, your request is sent in plain text to a domain name system (DNS) server, where a domain name like AppleVis.com is converted to a numerical IP address. With iCloud private relay enabled, however, your request is first sent to Apple, who can see your IP address but not your destination. Then, after assigning your request a new IP address, it is sent to a third-party content provider who can see your destination but not your original IP address, which is then sent to your destination; the idea being that no one entity involved in processing your request, from your ISP to Apple to the third-party content provider to your destination website, has a complete picture of who you are and what you’re up to.

While iCloud private relay can help mask your identity when browsing the web, which may sound similar to a common selling point for virtual private network (VPN) services, it is not a VPN service. Crucially, it only works in Safari, not other browsers or apps, and while it can optionally obscure your precise location from the sites you visit, it does not allow you to spoof your country, like many VPN services do.

Also, as it is currently in beta, reliability and performance on certain networks and websites may vary, particularly on school or office networks that restrict communication with remote proxy servers. To disable iCloud Private Relay for a particular network on iOS and iPadOS, when connected to that network, go to Settings > Wi-Fi, focus on your network and select "More info" from the actions rotor, and turn off the “limit IP address tracking" toggle; this setting can also be found in Settings > cellular > cellular data options to disable the feature when using cellular data. To do the same on macOS, when connected to that network, go to System Settings > Wi-Fi > Details, and turn off the “limit IP address tracking” toggle.

Advanced Data Protection

By default, some types of iCloud data, like backups, photos, and iCloud Drive files, are secured using an encryption key stored on Apple’s servers, so if you ever lost access to your account, Apple could assist you in recovering the data, provided you are able to prove your identity and ownership of the account. Other types of data, like saved login credentials and health information, are encrypted end-to-end, meaning no one, not even Apple, can access it, as the encryption key is only stored on devices signed into your Apple ID.

For added security, you can enable Advanced Data Protection in iCloud Settings on iOS, iPadOS, or macOS, which encrypts all iCloud data except for mail, contacts, and calendar end-to-end. This way, even if someone gained unauthorized access to Apple’s servers, they would not possess your encryption key, and thus your data would be indecipherable to them. For this reason, enabling Advanced Data Protection requires you to set up an account recovery method, either designating a trusted contact who can assist you in recovering your account, or generating a recovery key that can be used to decrypt your data if you ever forget both your Apple ID password and device passcode. For more information on Advanced Data Protection, check out the Apple Support article “How to turn on Advanced Data Protection for iCloud.”

iCloud.com

In addition to managing iCloud content and settings on your Apple devices, you can also manage some iCloud features and settings on the web by going to icloud.com on any computer. Here, you will find web apps for Mail, Contacts, Calendar, Find my, and more. However, accessibility of these web apps with Voiceover and other screenreaders is hit-or-miss at best, so I don’t recommend using them if you don't have to.

Conclusion

If you’ve read through this guide and thought, my devices already do the things described, great! This is how it’s supposed to work. If you have just set up iCloud, I hope the information in this guide gave you an idea of what you can do with it, and will ultimately help you make the most of the features that enable your devices to work best together.

More information can be found on Apple's iCloud overview page, and you can post a comment if you want something clarified in this guide.