From iTunes on your computer, open the Store menu, select "Turn on iTunes Match, " enter your Apple ID and password and click Subscribe.

WSJ: iTunes You Can Use

Once you set up iCloud using your Apple ID, any content that you buy from the iTunes Store will show up on other devices without any syncing.

WSJ: iTunes You Can Use

After all, in order to activate an iPhone, iPad, or iPod, you need to have an Apple ID and that means you need a credit card even if you only want to redeem an iTunes gift card.

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