Here is the page of iTunes USA retailer
iTunes USA
iTunes USA
3 Avios per $1

iTunes USA

When will I get my Avios?

PurchaseToday
Tracked within information5 day(s)
Awarded within information30 day(s)
Rewards apply to all paid content.

Stated reward is for iTunes books, TV, movies, iOS in-apps and in-app subscriptions. You will earn a lower reward on purchases of music, playlist or ringtones. Purchases of iTunes Gift Card are not eligible to earn rewards.

You cannot earn rewards for purchasing hardware through the iTunes program or on Donations.

All In-App Purchases made in a 24-hour window in that same app will be eligible to earn rewards.

Your purchase will be shown in your account around 14 working days from the date of your purchase.

Effective 4 Aug 2014, iTunes will not entertain enquiry on untracked iTunes transactions.

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Rewards are not calculated on postage / handling / delivery costs or associated purchase taxes in your region (This may include but not be limited to VAT, GST etc).

About iTunes USA

iTunes is a free application for Mac and PC. It plays all your digital music and video. It syncs content to your iPod, iPhone, and Apple TV. And it’s an entertainment superstore that stays open 24/7.