The new service appears to work like many other online photo repositories: You've got the ability to add photos to you Amazon Cloud Drive from the web, your mobile device. There are mobile apps for iOS and Android.
On early inspection, the service is pretty slick, meaning, just as refined as we'd expect from any cloud syncing service. You take a photo on your phone—it's in the cloud forever. Want to upload your existing library? Its an easy drag and drop interface that's very similar to the easy services we have seen from competitors like Dropbox and Google. Hell, it even supports RAW files.
Amazon Prime has always been a good deal, and the company just keeps tacking on more and more value to make it an unbeatable deal. Consider that many people pay extra money to store their photos online. I personally pay $10 for a Dropbox, even though Flickr is free. Other people pay extra money for bonus storage from iCloud or Google Drive. Amazon is something I already pay for, and it's become increasingly clear that cloud storage is basically a free commodity at this point, and so Amazon, with its infinity cloud servers, is doing the sensible thing and giving it away for exactly what it costs. And that's great for you. [Amazon and Amazon via The Verge]