About backups for iOS devices - Apple Support

https://support.apple.com/en-us/ht204136

About backups for iOS devices

Decide which method is best for you

This article can help you decide which backup method is best for you. In case you ever need an alternative backup, you can make a backup in iCloud and another in iTunes.

iCloud backups

With a Wi-Fi network connection, you can make a backup of your device using iCloud. You don't need to plug your device into a computer or even be at home to back up with iCloud. 

iCloud backups include nearly all data and settings stored on your device. iCloud backups don't include:

• Data that's already stored in iCloud, like Contacts, Calendars, Notes, My Photo Stream, and iCloud Photo Library
• Data stored in other cloud services, like Gmail and Exchange mail
• Apple Pay information and settings
• Touch ID settings
• iCloud Music Library and App Store content (If it's still available in the iTunes, App, or iBooks Store, you can tap to re-download your already purchased content.)

Learn how to make an iCloud backup or how to manage iCloud storage and delete backups that you no longer need.

iTunes backups

From your Mac or PC, you can make a backup of your device in iTunes. Syncing your device with your computer isn't the same as making a backup. An iTunes backup includes nearly all of your device's data and settings. An iTunes backup doesn't include:

• Content from the iTunes and App Stores, or PDFs downloaded directly to iBooks (You can back up this content using Transfer Purchases in iTunes.)
• Content synced from iTunes, like imported MP3s or CDs, videos, books, and photos
• Photos already stored in the cloud, like My Photo Stream, and iCloud Photo Library
• Touch ID settings
• Apple Pay information and settings
• Activity, Health, and Keychain data (To back up this content, you'll need to use Encrypted Backup in iTunes.)

Learn how to make backups in iTunes, how to find them on your Mac or PC, and how to delete backups that you no longer need.

Can I use my device's backup for another kind of device, like an iPhone backup for an iPad?

While you can restore a device from a backup of another kind of device, like using an iPad backup for an iPhone, certain types of content won't transfer. This content includes photos, Messages, attachments in Messages, Voice Memos, and apps that aren't compatible with the device that you're setting up. For example, apps compatible only with iPad won't transfer to your iPhone.

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