The iTunes backup doesn't make extra copies of any media files, though, so films, music, and apps bought from iTunes will need to be downloaded again from the site or your PC. (The iPhone/iPad will do this automatically when you restore from the backup, however.)
Creating an encrypted backup in iTunes
There's one additional type of backup available in iTunes, which is an encrypted one. If you have sensitive data on your phone, or are just safety-minded, then choosing this option will give you an added layer of security by making the backup accessible only through a password that you'll be prompted to create.
You do an encrypted backup in the same way as an unencrypted one - either automatically or manually, only with the encrypt option ticked. The first time you do this there will be an extra step in which you select a password.
Do remember, though, that this password will not be known to Apple, so if you forget what it is, your backup will become useless. Due to the extra security levels of an encrypted backup, Apple adds additional data which is withheld from the standard version. This includes information from the Health app, alongside your password keychain.
If you've got an Apple Watch: Make sure your backup is encrypted!
If you're anything like us (allergic to any more hassle than the bare minimum) you might be thinking that encrypted backups sound like more trouble than they're worth. (In fact remembering a password isn't a lot of trouble, although you may find that the first password you try isn't accepted.) But Apple Watch owners in particular should grit their teeth and pick the encrypted option.
Apple could probably make this clearer (you'll see in the screenshot above that it mentions only "passwords, Health and HomeKit data"), but the health data that is backed up when you do an encrypted backup, but not when you do a standard backup, includes all your Apple Watch exercise data: your achievements and running times and the rest of it. The allure of Apple's motivational trickery is such that losing this data can be extremely distressing, not to mention inconvenient if you're in the middle of a programme of self-improvement. An encrypted backup is your friend.
If you did an unencrypted backup when moving from one iPhone to another, wiped your Apple Watch and then paired it with the new iPhone and discovered all the exercise data is gone, don't panic.
The exercise data should be stored on the old iPhone (you didn't wipe it yet, did you?), so if you wipe the new iPhone, do another backup of the old iPhone (encrypted this time), restore the new iPhone from that backup, wipe the Apple Watch and pair it to the new iPhone... after all that, you'll find that the badges and running times have all come back.
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