Reader Stephanie Johnson has a question regarding an old and new iPhone and the apps they hold. She writes:
I have a 64GB iPhone 5, and there’s a recall to fix a fault sleep/wake button. Apple says it will give you a 16GB loner for the few days it takes to repair. What’s the best way to create a temporary, scaled-down version of your phone to use on the loaner, while keeping your app organization structure intact when you revert to your original phone again?
As you’re assuredly aware, the difficulty you face is that your 64GB phone likely has more stuff stored on it than a smaller-capacity phone can handle so you can’t simply back up your current phone and then restore it to this new device. Although you could approach this by setting up the loaner phone with your Apple ID and retrieving just those apps you need, I'm going to suggest instead that you use a tethered iTunes connection as you can more easily get to your existing data and apps. The result will be a phone that has the apps and data you need in the short-term, but not a fully restored copy of your old phone.
As you’re going to have a temporary phone in your life for awhile, let's start by creating a just-as-temporary iTunes library for the loaner phone. Here’s what I’d do.
Start by backing up your iPhone to your Mac via iTunes. To help ensure that all the apps within iTunes are up to date, choose View > Show Sidebar, Control-click (right-click) on the iPhone’s name in the now-exposed sidebar, and choose Transfer Purchases. Once those apps have been transferred choose File > Devices > Backup. You do this not only because you may need to return your now-fixed phone to its last-saved state, but you’ll want to be sure that the loaner phone has the most up-to-date versions of the apps you put on it.
And then there’s your iPhone’s data. On the phone destined for the shop be sure to turn on iCloud syncing for any data that you’ll want to use on the loaner phone. If there are specific documents within apps that you intend to use, you’ll need copies of them as well. One way to approach this is to save a copy into a cloud service—iCloud, Dropbox, Google Drive, or Box.com, for example. If an app doesn’t support cloud syncing, you can select your iPhone in iTunes, choose the Apps tab, scroll down to the File Sharing area, select the app that holds those documents, and in the Documents area to the right, drag the documents to the Desktop to make a copy.
Now select the Apps entry in iTunes’ sidebar, Control-click (right-click) on any app that appears in the main window, and choose Show in Finder. This will expose the contents of the Mobile Applications folder within your iTunes Media folder. Leave that window open and quit iTunes.
When you have the loaner phone, connect it to your Mac, hold down the Mac’s Option key, and launch iTunes again. A dialog box will ask you to locate an existing iTunes library or create a new one. Choose to create a new library.
iTunes will open and ask how you’d like to configure your phone—by restoring it from an existing backup or configuring it as a new device. Given that the contents of your existing backup is likely to exceed the capacity of this 16GB phone, choose to set it up as a new device. If iTunes’ sidebar isn’t open, choose that Show Sidebar command I mentioned earlier.
Return to the Finder and within the Mobile Applications folder that’s still open, select the apps you want on the new phone by Command-clicking on them, and then drag them into the top portion of iTunes’ sidebar (where it reads Music, Movies, TV Shows, and so on). The apps will be added to the new iTunes library. Once they’ve all been copied to the library, sync them to the loaner phone as you normally would.
Now, create your iCloud account on the phone so you have access to its synced data. Configure any other accounts that you wish to use with the phone—a Gmail account, fo example. And finally, retrieve any documents you synced to the cloud or copied to your Mac and place them on the phone.
When it’s time to return the loaner phone and reacquire your old one, sync any new documents and data you've created on the loadner phone to the cloud or your Mac. Then wipe the loaner by going to Settings > General > Reset > Erase All Content and Settings. With your returned phone attached to your Mac launch iTunes again with the Option key held down and click Choose Library. Locate your old iTunes library and open it. If the contents of your returned phone was wiped out, jack it into your Mac and restore it from the backup you made before taking it to the shop.