Don't get this confused with the science fiction show by the same name, as Amazon's version helps you do one thing and one thing only: buy more Amazon stuff.

To use Firefly, you open the app and it fires up the camera. Point your camera at anything, like a set of headphones or even a can of sardines, and it will attempt to link it to a product page on Amazon.

However, in testing this didn't really seem to work most of the time, if at all. This notion was OK in the US, it seems, but the UK version just wanted to look at barcodes.

Amazon Fire Phone review

Firefly doesn't just work on physical, tangible items that you can identify with the camera (in theory). When the app is fired up, it can also recognize music, movies and TV shows. As long as the phone can hear sound from your radio or TV, and it can pair it with something in Amazon's store, it will be recognized.

For example, if you're watching an episode of Friday Night Lights and you point the phone toward the TV and allow Firefly to see and hear the TV, it will tell you what you're watching along with a link to buy or watch episodes of Friday Night Lights on Amazon Prime.

Amazon Fire Phone review

The same goes for music. If you're itching to find the name of a song you're listening to, simply open up the Firefly app and place your phone near the sound source. If it's in Amazon's massive library, the song will pop up with an accompanying link to download or listen to the song.

Firefly is useful, in a sense, because you can identify a lot of things you don't recognize. If you've ever encountered an object, song or movie and wondered, "What on earth is this?" there's a good chance that Firefly could identify it for you.

But of course, like pesky ads in a free game, those little Amazon pop-ups poke you, begging, "BUY ME!"

Dynamic Perspective

I'm tempted to say that you can file Dynamic Perspective in the Useless Folder, but such a folder would be ironically living up to its own name.

It's a trick, a gimmick. Sure, it's neat to see stuff move around on your display when you tilt the Fire Phone, and it does give it a little bit of a 3D effect, but it's hardly functional.

Amazon Fire Phone review

Amazon argues that you open up a whole new world of stuff within the display, and you can dive a little deeper into content by peeking around or behind things. But there is absolutely no reason why you need to stuff four front-facing cameras to do this when you can do the same with finger gestures.

It also feels unnatural to tilt the phone around in my hand. I almost want to follow it around with my face, which would defeat the purpose of Dynamic Perspective.

As you can imagine, the degree to which you can tilt the device is very limited - start tilting it too much and your entire perspective is going to be nothing but bezel.

Amazon Fire Phone review

There are a few tricks that Amazon stuffed into Dynamic Perspective. One of those is in maps. If you have several pins or areas of interest that come up in a search, a slight tilt of the phone will reveal the names and/or ratings of each of those places.

Again, most of what you can do with Dynamic Perspective, which isn't much, can really be done with just your fingers. But if this is the best Amazon can come up with to distinguish itself and be unique, it isn't helping much.

It's not even that accurate, with the shifting and scrolling juddery and unresponsive. For something that requires FOUR cameras to achieve, it seems a complete waste of time.

In short, Dynamic Perspective is hardly a reason to buy the Amazon Fire Phone. Neither is Firefly. Both features are OK tricks, but that's as far as they go. In terms of usefulness and practicality in daily use, it varies dramatically, but I'm going to err on the side of being able to live without both.