Amazon launched the Fire in the US back in June, so it hasn't been a very long wait for it to arrive in the UK. Unless you've completely missed the news, it's Amazon's first smartphone and has a slew of exciting features, including 3D-like visual effects and a visual search which is said to identify 90 million objects. (See also: Amazon Fire phone launch: as it happened.)
Amazon Fire phone review: price and availability
The Fire Phone is exclusive to O2 - you can't buy it from Amazon.co.uk, and there's choice of pay-as-you-go or contract. If you opt for the former, the Fire phone costs £400 (for the 32GB model) or £480 for the 64GB.
Plump for a contract and the 32GB model is free if you pay a minimum of £33 per month, or £28 per month with a £40 up-front cost for the smartphone. If you want the 64GB model, the minimum price is £33 with a £50 up-front fee.
You can get a Fire phone right now.
Amazon Fire Phone review: build and design
If it had an aluminium band around the edge, the design would be reminiscent of the iPhone 4, since the Fire phone has flush glass front and rear panels. It also has a top-mounted headphone socket and sleep/wake button.
It's the same size at the new iPhone 6, though, with a 4.7in IPS screen. Resolution is slightly lower at 1280x720 pixels, which means 312ppi against the iPhone's 326ppi.
There are no buttons on the right-hand side but on the left are volume and a dual-purpose camera/Firefly button (we'll come to that in a moment).
At the bottom is a microUSB port for easy charging and synching, and there's a physical home button below the screen. Stereo speakers hide behind grilles on the top and bottom edges, and produce decent audio with good stereo separation.
It's a fairly chunky device, weighing 158g and being - as near as makes no difference - 9mm.
The only thing we don't like is that the four courner-mounted sensors - which look just like the front-facing camera - are very obvious, and make the phone a little messy looking. (See also: best smartphones: The best phone you can buy in 2014.)
Amazon Fire Phone review: specs and features
The Amazon Fire Phone is a 4.7in handset. That 4.7in display is an IPS LCD capacitive touchscreen. It has a resolution of 720 x 1280 pixels, giving it a pixel density of 312ppi. That's good, but not great in the current market.
It pairs a quad-core Qualcomm Snapdragon 800 CPU with 2GB RAM, so performance is well looked after. Onboard storage options are 32GB or 64GB, although there is no storage expansion slot. An onboard Adreno 330 GPU takes care of graphics performance.
It's a 4G LTE handset, with GPRS, EDGE, 802.11 a/b/g/n/ac dual-band Wi-Fi, Bluetooth 3.0, NFC and USB connecivity via a microUSB 2.0 charger/connector port.
In terms of media you get stereo speakers, and a 13Mp camera. The latter is a 13Mp camera capturing 4128x3096 pixels, optical image stabilisation, autofocus and LED flash. It can capture 1080p video at 30fps, and there's a front-facing 2.1Mp camera for selfies and video calls.
Amazon Fire Phone review: Fire OS
Although the Fire phone runs a similar operating system to Amazon's Fire tablets, this is basically a new OS in the smartphone world. It's based on Android of course, but you wouldn't know it: there isn't a single icon, button or font that's borrowed from KitKat or Jelly Bean.
If you've used a Fire tablet, you'll be right at home since navigation is very similar. You get a carousel of recent apps and content, and you swipe upwards to see all your apps. Swiping down from the top brings up a revised control centre and notification area. (See also: Amazon's Fire Phone shows that Kindle Fire failed.)
Selecting an item from the carousel displays context-sensitive options below it. Stop the carousel on the Silk web browser, for example, and you'll see a short list of recently visited websites. Rotate it to the camera and recent photos are shown, go to a game or app and you might see recent achievements or settings or options. You get the idea.
What's not quite as obvious is that you can swipe in from the right-hand side to display upcoming calendar appointments, a weather forecast and your 'VIP' contacts. Swipe in from the left and you get a new version of the menu bar which runs across the top on a Fire tablet, letting you quickly jump to your music, videos, photos, apps, games, documents.
Also in the list are Shop and Prime, but they're not the only way Amazon integrates its services. Tap on Books and you'll see a shopping basket icon at the top right: a quick way to jump to the Kindle bookstore. As you'd expect, it's the same in Apps, Games and Audiobooks. Tap on Videos and Amazon's Prime Instant service leaps into life.
While Amazon's selection of books and music rivals the best out there, it's a different story with apps and games. The selection is much better than it was a year or two ago, but you'll still find both big-name and more obscure apps missing.
For example, BBC iPlayer, Whatsapp, Real Racing 3, Waze, Just Eat, Fitbit and even the Nest smart thermostat app are all there ready to install for free. However, try to match the full set of apps you have on your iPhone or Android smartphone and you'll quickly find holes.
Internet banking apps are scarce, and you won't find any official Google apps such as Maps, Gmail or YouTube. There's still no 4 on Demand app, not ITV Player. If you also have a few smartphone-accessed gadgets, there's a good chance there's not yet an Amazon app available. A few which proved problematic for us included the Nike Fuelband, Y-cam HomeMonitor IP cameras, Parrot's Flower Power (a Bluetooth plant monitor) and the Tado smart thermostat.
Amazon Fire Phone review: Firefly
One feature which you won't find on a Kindle Fire tablet is Firefly. Firefly is the principal reason for the Fire Phone existing, and has been described as 'Shazam for the real world'. Using Firefly you can take pictures of just about anything, and the Fire Phone will extract the useful information in a semantic style. See a product you like, take a picture, and buy it.
Firefly uses the camera app to identify music, movies, TV episodes, books, games, DVDs and other products. It can also recognise printed text such as web addresses, email addresses and phone numbers, and let you tap to go directly to the website, send an email or call a number without typing a digit.
Firefly tended to work best with book and DVD covers, offering IMDB reviews as well as links to buy the item in Amazon's shop. It was also reliable for URLs and phone numbers.
Amazon Fire Phone review: 3D phone? Meet Dynamic Perspective
Firefly can be genuinely useful as well as a gimmicky tool which the cynical will view as just another way for Amazon to make money from Fire phone users. Dynamic Perspective, on the other hand, could be seen as pure gimmick as there's no sales tie-ins.
What is Dymamic Perspective? It's Amazon's name for the front-facing sensors which allow the Fire phone to create a kind of glasses-free 3D experience. From the wacky, cinematic 3D lock screens, which range from an under-sea shipwreck to a pinball machine, Amazon has tried to incorporate Dynamic Perspective just about everywhere in Fire OS 3.6.
The way it works is by sensing the position of your head relative to the screen, so moving your head or tilting the smartphone itself shifts the image on screen. There's a limited amount of movement, so you can peer to the right or left, up or down to see detail and objects that were previously off screen. In some apps (or the lock screen) it's almost like there's a larger screen hidden inside, and you're looking through a smaller aperture at it, seeing only a portion at one time. It's very odd.
From volume sliders and toggle switches to app icons, it seems that 3D is order of the day. Even menu text is 3D, which is just about ok for large fonts, but it just makes smaller text look blurry and quickly induces a headache.
There are a couple of pre-installed games which use Dynamic Perspective to good effect, although these appealed only to our child testers.
As the Fire phone has GPS, and there's no access to Google Maps, Amazon has come up with its own maps app. It looks and works much like Google and Apple maps, and we wouldn’t be surprised if it used data from Google maps. Dynamic Perspective allows you to change the angle of the map slightly, but it doesn't offer the range you get in Apple maps, for example. If anything, it's more akin to the parallax effect introduced for the wallpaper in iOS 7.
There are 3D outlines of buildings, as with Google maps, but only a few landmarks, such as the Gherkin, BT tower and Shard with textures. You can get driving and walking directions, as well as for public transport.
Amazon Fire Phone review: gesture navigation
We're yet to be convinced by Dynamic Perspective as a must-have feature in a smartphone, but we do like the gestures.
In virtually every app, you can swipe in from the right or left - sometimes both - to show menus and other context-sensitive information or options. These can be invoked by tilting the phone left or right, and dismissed by tilting the other way. It works reliably, too.
Another feature - albeit one we've seen before - is auto-scrolling. However, rather than use Samsung's technique and try to track eye movement, Amazon's works by tilting the Fire phone up or down slightly. The more you tip, the faster a web page, for example, scrolls.
If you rotate the phone left or right (the swivel gesture), this displays the control centre offering quick access to the torch, Mayday - the live tech support service - and notifications.
Finally, there's Peek, which shows extra information when you very slightly tilt the handset. Amazon says you can see the date a photo was taken, but this didn't work when we tested it. It can also be used by any app which chooses to implement it, but when browsing clothing in Amazon's shop you can see a larger image of the item, for example.
Amazon Fire phone review: digital assistant
One feature that Amazon has kept quiet is the Fire phone's un-named digital assistant. It's clearly a work in progress, but this Siri-like butler has an English accent and can search the web, send messages and make phone calls. Those core features are useful, though, and it means you can dictate messages - recognition accuracy was as good as we've come to expect from today's smartphones, and Amazon's system is as good as Siri in that respect, even adding punctuation if you dictate that too.
If a contact's name is an usual spelling, speaking the full name - including surname - ensures the transcription is correct.
Amazon Fire phone review: cameras
Camera quality is increasingly important as smartphones take over from traditional digital cameras. The specs are impressive: 13Mp on the rear, with optical stabilisation, and 2.1Mp at the front.
While the front snapper is nothing special - it's fine for the odd selfie and Skype chats - the rear is pretty good. Images have realistic colours and are generally sharp and detailed. It's only when you zoom in and scrutinise quality that you'll find a lot of compression and smudgy textures. Plus, the quality in low light isn't great.
Here's our usual shot of St Pancras, resized to 1200 pixels but otherwise unedited. Click it to enlarge:
Here's a 100 per cent crop of the original version of the photo above so you can see the soft detail (you can't click to enlarge as this is actual size)
The Fire phone can take a decent photo if you try hard: this is a cropped image which show it is capable of sharp detail and reasonable macro.
In low light, though, there's a lot of noise (click to enlarge and see it better):
Video is good, too, and the stabilisation works a treat. Don't try cinematic pans, though, as the system tries to keep the image still, resulting in jerky footage.
The camera app is shared with Firefly, which can be confusing. A long press of the dedicated shutter button starts Firefly, while a short press - even in sleep mode - wakes up the camera app. HDR is suggested automatically based on the scene, and there's a panorama mode too. A strange Lenticular mode allows you to take up to 11 photos from slightly different angles, resulting in a stilted animation which you can only view on the phone itself.
Amazon Fire phone review: verdict
We've asked the question before, but is there room for yet another smartphone operating system. Amazon is pinning its hopes on the Fire phone, clearly, but if designed to be a portal to all things Amazon - which it is - then why is it so expensive?
For roughly the same money, you could have a flagship Android smartphone or for a little more per month on contract, a brand new iPhone. If you're looking purely as specs, the Fire phone is fairly mid-range. The deal is sweetened by a year of free Amazon Prime, though, which would otherwise cost you £79 and includes next-day delivery and the Instant Video streaming service.
So the Fire phone has a few things going for it, but asking people to get to grips with a new operating system, deal with the limited app store and still pay top dollar for it is a bold move indeed.
Ultimately, the safe option is to plump for an Android device such as the LG G3. (See also: best smartphones: The best phone you can buy in 2014.)