: Always back up your iPhone to iCloud or a computer before handing it over for service.
If you have a cracked screen, you can often get it fixed the you bring it in. Because they are authorized, any work done at Best Buy is backed by Apple and won't void your original warranty. Service Options & Pricing best buy fix iphone screen
: You will need to disable "Find My iPhone" before technicians can begin the repair. : Always back up your iPhone to iCloud