How to Use iTunes for Two iPhones So Information Will Not Mix

You can synchronize multiple iPhones -- along with other Apple devices -- with a single computer, through the iTunes multimedia management software which creates a backup of the device's content and settings. Each iPhone has a separate backup, as long as it has been set up as a different device from the other iPhones you sync with your computer. The iPhones must be connected to the computer independently of each other and at different times, however, as iTunes is unable to synchronize more than one device at a time.

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The iPhones must share the same iTunes account to be synced with one computer.

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Launch iTunes on your computer by clicking its icon on the desktop.

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Connect your first iPhone to the computer using its USB cable. ITunes will automatically detect the iPhone and add it to the "Devices" list in the left-hand column.

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Double-click the entry for the iPhone in the iTunes "Devices" list. Its name will be highlighted and a cursor will appear in the iPhone's name.

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Type a unique name for the iPhone that will differentiate it from any other iPhones or Apple devices you want to sync to the computer.

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Open the "Summary" tab in the main iTunes window and click the "Sync" button. The iPhone will be backed up onto the computer. Disconnect it once the synchronizing completes.

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Connect your second iPhone to the computer. It will appear on the iTunes "Devices" list.

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Double-click the name for this iPhone, and give it a unique name as well. Sync the iPhone before disconnecting it.

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Repeat this procedure for any additional iPhones or Apple devices you want to sync to the same iTunes installation on your computer.