Q: I am moving from an iPhone 4S up to an iPhone 5. I want to transfer everything over and then wipe the old phone and give it to my sister. Both phones are unlocked. Where do I start?
A: The first step is obviously to transfer all of your data from your iPhone 4S to your new iPhone 5. This is relatively straightforward and simply involves backing up your iPhone 4S and then restoring that backup onto the new iPhone 5. This can be done either using iTunes on your Mac or Windows PC or over-the-air using iCloud, and you can find more detailed information on how to do this in our article on Transferring your Content to a new iPhone, iPad or iPod touch.
We generally recommend using iTunes as it’s not only considerably faster to transfer your data over a direct USB connection with your computer, but chances are you will end up having to sync with your iTunes library anyway to restore items such as music and videos that were not purchased from the iTunes Store. The iTunes method also allows you to transfer all of your passwords for things such as e-mail accounts and Wi-Fi networks to the new device, providing you do so via an encrypted iTunes backup. You can enable the encryption option by connecting your iPhone to your computer, selecting the “Encrypt iPhone backup” option, and then manually making a backup via the “Back Up Now” button.
You will be prompted to set a password for the encrypted backup, and will need to supply this password when restoring your backup onto your new iPhone 5. Note that you only need to use encrypted backups to transfer passwords when moving between devices; by default passwords are stored in your backups using a hardware-specific encryption key, so they can always be restored back to the same device regardless of whether your backup is encrypted or not.
As detailed in the article above, transferring the data onto your new iPhone is pretty straightforward; simply select the appropriate option as part of the iOS Setup Assistant on your new device. Alternatively, if you’re using iTunes you can actually skip the setup assistant and just plug it directly into iTunes to restore it from there.
Since the iPhone 5 uses a different type of SIM card (nano-SIM) from the iPhone 4S (micro-SIM), at some point during this process you’ll need to transfer your cellular account over to a nano-SIM card for your iPhone 5. It doesn’t really matter whether you do this before or after you restore your device, as it primarily only affects your cellular data access and where phone calls come in. iMessage and FaceTime registration for a phone number on your new iPhone 5 will require a valid cellular account as well, but this occurs whenever you restart the iPhone or re-insert the SIM card.
Once you’ve restored your data onto your iPhone 5 and are confident that everything is working properly, you can erase your old iPhone 4S, which effectively returns it to an out-of-the-box factory configuration, and then hand it off to your sister for her use. From that point, she simply sets it up as if it were a brand new iPhone that she purchased from an Apple Store or carrier store, arranging for cellular service and providing a micro-SIM card for it as necessary.