Once you download Amazon Cloud Drive Photos and sign in with your Amazon account, all of your albums will be viewable from the app. If you don't have any items stored on your account yet, you can simply toggle to the Device view (button at the top of the screen), and upload any of your locally stored photos to the cloud with a long press. It's worth noting that while you can upload entire albums at once, the app does not let you pick and choose multiple photos to upload in a batch, which is frustrating.
While Photos' biggest strength is undoubtedly its simplicity, its biggest weakness might be that it is, in fact, too simple. To start, the app doesn't let you rename photos or albums, which means it's not a very good tool for organizing your Cloud Drive. And while it's great at saving locally stored photos to the cloud and vice versa, it doesn't let you move items among specific folders, or even choose a destination folder, which again highlights the app's lack of organizing capabilities. Lastly, if you have a hefty number of photos stored on your account, then it might be difficult to find them, as there is no built-in search function. Sure, the app lets you sort albums by date, but that's about all the help you get.
One feature that users, including myself, are already clamoring for is auto-upload. The Google Drive and Dropbox apps both let you automatically upload photos to the cloud as they're taken on your device, while Amazon's offering doesn't. That said, I'm predicting that Amazon is already hard at work, adding the feature into a future update.