Every time you make a purchase that charges your credit card, iTunes or Google Play sends you all your purchases receipts directly to the
e-mail address you have registered in your iTunes or Google Play account.
So, an easy way to check for your receipts is to check your inbox for the e-mail address you have registered to your iTunes or Google Play account!
If you are unable to find the receipts on your e-mail inbox, you can always check for the receipts directly on iTunes or Google Play.