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Perhaps the biggest selling point of the Sony Xperia Z3 Compact is how well Sony has managed to fit most of the features, specs and overall experience of the Sony Xperia Z3 into a smaller and cheaper handset.
Often a smaller variant of a flagship smartphone comes with a number of compromises that keeps it from reaching the lofty heights of its larger brethren. For example, the HTC One Mini 2 has a 1.2GHz Snapdragon 400 processor and 1GB of RAM,compared to the full size HTC One M8's 2.3GHz Snapdragon 801 and 2GB of RAM.
Feature parity
It's to Sony's credit, then, that the Sony Xperia Z3 Compact doesn't suffer from such large discrepancies compared to its bigger sibling.
Both feature a 2.5GHz quad-core Snapdragon 801 processor along with an Adreno 330 GPU. Both feature the same camera as well, with a 20.7MP Exmor RS sensor with a 25mm G Lens and ISO 12800 settings.
That doesn't mean they're both identical in specs, and there have been compromises. While the Xperia Z3 comes with 3GB or RAM, the Z3 Compact has to make do with 2GB, still more than enough for most uses, and it's still double the RAM you'll find in Apple's more expensive iPhone 6.
Regardless of that, Sony has done a great job of making sure you don't feel penalised for going with the smaller phone.
Brighter screen
Another key feature of the Sony Xperia Z3 Compact is the screen. Sony is a huge company with a lot of fingers in a lot of pies. While this hasn't always worked in Sony's favour, it has its upsides, with technology from its TV and camera divisions winding up in the Xperia Z3 Compact.
These features include proprietary Sony technology found in its Bravia TVs, such as Triluminos and Live Colour LED, which make the colours as vibrant as possible on the Z3 Compact. Cutting through the marketing speak, what this leaves us with is a very impressive looking display that does deliver on vivid colours.
Viewing angles of the IPS screen are also good, though best results are still when viewing the display head on. Brightness levels of the display have also been boosted, with the Z3 Compact's screen able to reach 600nits, compared to the 460nits of the Xperia Z2.
Taking the Sony Xperia Z3 Compact outside, even in bright direct sunlight, I was still able to view the screen without any problem. This is a really brilliant upgrade that has excellent real world benefit.
However, with the screen another compromise has been made with the shrunken down handset. While the Xperia Z3's 5.2-inch display can handle full HD 1,920 x 1,080 resolution, the Z3 Compact's 4.6-inch display only reaches 1,280 x 720.
I say "only" but that resolution on the Z3 Compact's 4.6-inch screen results in a pixel density of 319ppi (pixels per inch). This is a fairly decent level of pixel density (the iPhone 6's 4.7-inch 1,334 x 750 screen equates to 326ppi for comparison), and image quality was sharp and clear.
Some have been a little disappointed that Sony didn't go for 1,080p on the Z3 Compact as well. While that would have been nice, the truth is that the benefits of such a resolution are fairly limited on sub-5-inch screens.
Sony apps
The appeal of the Sony Xperia Z3 Compact's final key feature will vary depending on how much of a Sony fan you are. Sony's handset is closely integrated with a number of Sony services, most obviously the Sony Entertainment Network. This is comprised of the video streaming and rental service PlayStation Video and the PlayStation Network.
Since our original Xperia Z3 Compact review, Sony has shuttered its Music Unlimited service and agreed a deal to funnel Spotify through its Walkman app, so there's no longer the same separate Sony music app to consider here. This is a good thing.
If you're heavily invested in the Sony ecosystem, then you'll probably be quite pleased. However, if you already have a Netflix account for movies or a non-Spotify music streaming account, then Sony's offerings won't be of much interest, and there's little to encourage to ditch your subscriptions and go with Sony.
Of course you can get Netflix, Google Play Music (which also comes pre-installed) and other apps on the Xperia Z3 Compact, but it then leaves you with a number of Sony's own apps that will sit there uselessly.
Remote Play
As with its bigger sibling, the Sony Xperia Z3 Compact features Remote play, which lets PlayStation 4 owners stream games from the console to the Z3 Compact.
Being able to stream console quality games to the Z3 Compact almost sounds too good to be true, and when the Xperia Z3 Compact initially launched without the Remote Play feature, I was slightly concerned that it might come in a potted-down version… or worse, not at all.
However it didn't take Sony that long to implement the feature, which is just as well as Remote Play proves to be an excellent addition to the Xperia Z3 Compact, making Sony's latest handset even more desirable.
Setting up Remote Play is relatively simple. All I needed to do to enable the feature was to download the Remote Play app from the Google Play store. Once downloaded, I turned on the PlayStation 4 and enabled Remote Play. This gave me a code that I could then type in to the Xperia Z3 Compact to securely log in to the PS4.
I also needed to pair the DualShock 4 controller to the Z3 Compact via Bluetooth. Sony's earlier attempts at using PlayStation controllers with its mobile phones had to be done using a cable, so going wireless is a big improvement – especially as Sony didn't sell the aforementioned lead and didn't explain where to get it.
It can make things a little complicated in other ways, however, as you need to unpair the controller with the PS4 before you pair it with the Z3 Compact. If you don't, and the PS4 is still in range, then the PS4 logs out and the Remote Play session is cancelled.
After using the DualShock 4 with the Z3 Compact you then need to re-pair it with the PS4 if you want to play your console directly. It's relatively straightforward but the process could be simplified and better explained – unless you just buy another controller, which kind of defeats the point.
However I had no complaints at all about the quality of Remote Play with the range of games I tried, which included GTA V and Assassin's Creed: Unity. Even when using Remote Play on another floor of the house, Remote Play worked smoothly.
It wasn't flawless, and when other people were using the Wi-Fi network there could be occasional stutters and graphical artefacts, but with a strong Wi-Fi signal I was very impressed.
There was very little input lag whilst playing, which means hardly any delay when using the controller. This is essential for fast-paced action games where every button press is important.
The fact that each game worked well impressed me a great deal. Sound is also streamed through the Z3 Compact's speakers which offer good quality, though audio quality is improved with headphones.
The Z3 Compact's 720p screen means the games aren't quite as impressive looking as on the Z3's 1,080p display. However, because of the smaller screen size of the Z3 Compact games still look vibrant and sharp, partly thanks to the additional display technology Sony has shoved in there to offset the lower HD resolution.
At 4.6 inches the Z3 Compact's screen isn't exactly tiny, but although it does a fine job displaying Remote Play games, if you're thinking of buying a Z3 Compact or Z3 mainly for Remote Play, then you might want to consider going for the larger Z3.
You can also use the touchscreen to control games. This displays a transparent overlay of the DualShock 4 controls on the screen, and it works OK.
However, the Z3 Compact's screen is a bit too small for the feature, so you'd be better off using a physical controller.
Overall I was very impressed with Remote Play on the Xperia Z3 Compact, which is easy to set and up works really well. Being able to stream your PlayStation 4 games to the phone while the TV is being used for something else is a fantastic feature.
It works just as well as on the more expensive Xperia Z3, although the larger screen size and higher resolution of the Z3 gives it a slight edge. However if you've got a PlayStation 4 and fancy playing your games remotely (but not too remotely – Remote Play for the Z3 Compact at the moment only works with Wi-Fi), then the Xperia Z3 Compact easily fits the bill.
Matt is TechRadar's Managing Editor for Core Tech, looking after computing and mobile technology. Having written for a number of publications such as PC Plus, PC Format, T3 and Linux Format, there's no aspect of technology that Matt isn't passionate about, especially computing and PC gaming. He’s personally reviewed and used most of the laptops in our best laptops guide - and since joining TechRadar in 2014, he's reviewed over 250 laptops and computing accessories personally.