iCloud Photos works in conjunction with the Photos app to securely store your photos and videos on iCloud, and sync them to your iPhone, iPad, iPod touch, Mac and Apple TV, as well as to iCloud.com. For example, let’s say you have an iPhone, an iPad and a Mac. You can take a picture on your iPhone and see the same picture on your other devices and on iCloud.com.
Amazon Photos lets you back up, organize and share all your photos, videos under 5GB and other files from your phone, computer or other device. You can access all your photos from virtually any device and share them with family and friends.