TL;DR:Through Oct. 78+ adult movies - watch free full movies and download uploading and backing up photos through Amazon Photos gets you a free $15 credit to use during Amazon's upcoming Prime Big Deal Days sale.

If you think about it, any discount on an item ever is technicallyfree money if you would have purchased that item at full price anyway. But during Prime Day specifically, Amazon also hands out free money in a much more direct way: through free promotional credits.

One of the first we've seen this fall Prime Day season is a revival of the Amazon Photos promotion. Newcomers who upload and back up their photos will be paid with a $15 credit that can be used during Prime Big Deal Days.

The offer is only eligible to new users who are uploading to and turning on Auto-Save through Amazon Photos for the first time, and the credit is only eligible for purchases made between Oct. 10 and Oct. 12. Just complete the promotional guidelines before Oct. 7 and, over the next few days, check your inbox for instructions on how to apply the credit to your Amazon account.

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Amazon Photos is included for free with any Prime membership and unlocks unlimited full-resolution photo storage. Photos can be easily accessed on any device logged into that account and displayed via a quick Alexa command on Fire devices or TVs.