Planning for your new iPhone
Will you need a new SIM?
If you have an iPhone 4s or older, and you’re getting a new iPhone 5 or newer, then you will need a new SIM. (What model iPhone do you have?)
If you need a new SIM card, usually you can go to your carrier’s store with your current and new phones and they will swap the SIM for you. But if your phone is under someone else’s name on a family or business plan, contact your carrier (AT&T, Verizon, etc.) to find out how to get a new SIM card.
Decide what to do with the old device.
You can trade-in your phone for instant credit with Apple: See https://www.apple.com/iphone/trade-up/
You can sell it to Gazelle at gazelle.com. Even non-working iPhones may be worth something.
Or you can use it as a wi-fi device without a SIM.
Just before you get the new iPhone
Save any important photos and videos from Messages to the Camera Roll.
Usually Messages are restored, but often old messages are lost. Copying important photos to the Camera Roll means at least you have saved the images.
If you have an Apple watch, unpair it from the old iPhone.
Unpairing it makes a backup of your Apple Watch, so you can restore it when you pair the watch to a new phone. Unpairing is the only way to make a backup of your Apple Watch.
Back up your iPhone to iTunes or iCloud.
The fastest way to get your data on your new phone is to restore from an iTunes backup. (Note: when you connect your phone to iTunes it will first sync. After the sync finishes, do a backup.)
Apple's instructions for moving your data to a new iPhone have detailed instructions about how to make a backup.
Finally, make sure you have the right passwords.
You will need the AppleID (usually an email address) and password for your phone’s data (contacts, calendar, etc.) and, if different, the AppleID and password that you use to purchase apps and media from iTunes.
After you get your new iPhone
As mentioned above, the quickest way to get your new iPhone up and running is to use iTunes to make a backup of your old iPhone and to use iTunes to “restore” that backup to the new phone.
You have to do a few things with your new iPhone before you can restore your data. The set-up screens will walk you through this process; enter your location and activate the phone (do this in the store to make sure the phone is working).
After that, you will see a screen for “Apps & Data”. Here you are given four options: Restore from iCloud Backup, Restore from iTunes Backup, Set up as New iPhone, Move Data from Android.
Apple's instructions for moving your data to a new iPhone have detailed instructions about how to restore your data from an iTunes backup or an iCloud backup, but if you tap “Restore from iTunes Backup” the onscreen instructions will walk you through the process.
If you have an iCloud backup, tap “Restore from iCloud Backup.” It will work just the same, but it often takes longer because everything has to be downloaded from Apple’s servers.