Confirming earlier rumors, the Fire Phone has a 3D-like screen. Amazon calls it Dynamic Perspective: basically, as you move the phone in your hand, the elements of the operating system on the screen move to create the appearance of depth.
To achieve the 3D effect of Dynamic Perspective, there are four corner cameras on the front of the device, each with an infrared light to combat the dark, and also a huge image database to "train" the tool's algorithms.
A new service introduced with Fire Phone is called Firefly. It's a mix of Google Now, Siri, and a bar code scanner. You'll be able to search for products by snapping a photo of them, search for music by playing it into the microphone, and more. The phone has a dedicated button to launch the service.
Amazon's Mayday feature is baked in to the Fire Phone. Introduced last year with the new Kindle Fire tablets, Mayday connects you with a customer service representative if you need help on your device.