When you update your billing information in the iTunes, iBooks, and App Store, or add a member to your Family Sharing group, a temporary authorization hold for a nominal amount is placed on your credit card or the payment method that you have on file. Like many other merchants, iTunes uses authorization holds to confirm that your payment account is active and has the funds available for purchases.
For example, in the United States, you might see a $1.00 USD authorization hold. If you live in another country, you'll see a charge for a similar amount in the standard currency of your region.
About the authorization hold period
Authorization holds are removed by your card issuer after a short time. The exact time it takes to remove authorization requests varies by financial institution.
If you use a debit card, you might see authorization holds as charges on your online statement. These charges are automatically reversed by your financial institution.
If you have questions about the way your card handles authorization requests, contact your financial institution.
See your actual charges in iTunes
On a Mac or PC, you can see your purchase history in the iTunes, iBooks, and App Store.