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Samsung Galaxy Alpha
The one obvious direct comparison to draw is with the Samsung Galaxy Alpha, another example of a compact handset with 2014 flagship specs. While Samsung has officially discontinued the Alpha (ahead of its time, we might add), it can still be picked up brand new for between £300 and £400 - a similar price range to the Z3 Compact.
The Z3 Compact's measurements of 127 x 64.9 x 8.6mm make it smaller if thicker than Galaxy Alpha at 132.4 x 65.5 x 6.7mm. However, the Samsung is a fair bit lighter than the Sony at 115g versus 129g. The weight discrepancy can probably be put down to the Z3 Compact's chunkier, more rugged, sealed off build and twin Gorilla glass surfaces. The slim Galaxy Alpha has a metal rim, but a largely plastic body – including a particularly flimsy removable back cover.
Both feel plenty classy in the hand, but the Z3 Compact's build quality, slightly heavier weight, and glass rear perhaps gives it the slightest of edges. Both smartphones have a 1,280 x 720 resolution screen, though due to the Z3 Compact's slightly smaller screen size (4.6-inches compared to the Galaxy Alpha's 4.7-inch), the Sony manages to have a slightly sharper image.
Both offer snappy general performance and similar Geekbench benchmark results. The Galaxy Alpha comes with Samsung's own quad-core Exynos processor and 2GB of RAM. One big advantage the Z3 Compact has over the Galaxy Alpha is its OS, which is far more faithful to stock Android 5.0, and thus superior to Samsung's overly fussy TouchWiz UI.
- Read our in-depth Samsung Galaxy Alpha review
HTC One Mini 2
The HTC One Mini 2 is another small variant of a popular flagship device, and again is available for a similar price to the Xperia Z3 Compact. The HTC One Mini 2 is both larger than the Xperia Z3 Compact (with dimensions of 137 x 65 x 10.6mm), and more heavy at 137g. Also like the Xperia Z3 Compact, the HTC One Mini 2 has a similar design to its bigger brother.
It comes with the same 1,280 x 720 resolution as the Xperia Z3 Compact, but with a slightly smaller 4.5-inch screen that results in a 326 ppi pixel density, compared the Z3 Compact's 319ppi.
HTC downgraded a number of components in the HTC One Mini 2 compared to the HTC One M8, with a 1.2GHz quad-core Snapdragon 400 processor, which makes Sony's decision to keep the same quad-core 2.5GHz Qualcomm Snapdragon 801 processor that's found in the bigger Xperia Z3 all the more laudable. Both miniaturised handsets do get a cut in RAM, however, though the cut from 2GB to 1GB for the HTC One Mini 2 feels a bit more savage than the Xperia Z3 Compact's cut from 3GB to 2GB.
- Read our in-depth HTC One Mini 2 review
The pricing of the Xperia Z3 Compact puts it in an unusual position. Despite recent online price drops, its recommended price makes it more expensive than most sub–5-inch handsets. Its biggest competitor in the sub–5-inch category, however, is the iPhone 6. This might not seem entirely fair, as the iPhone 6 costs a good £100 to £200 more than the Xperia Z3 Compact, but comparisons may be inevitable due to those superior specs and similar sizes.
Both have similar size screens, with the iPhone 6 just edging it with a 4.7-inch display. With a resolution of 750 x 1334 that results in a pixel density of 326ppi, higher than Sony's 319ppi, you get a clearer and sharper image on the iPhone 6.
On paper the specs between the two phones should give the Xperia Z3 Compact the edge, with the iPhone 6 being powered by 1GB of RAM and an 1.4GHz ARM-based CPU. However comparisons aren't that clear cut, as through a number of hardware and software enhancements, the iPhone 6's performance easily rivals the Xperia Z3 Compact's.
The same can be said for the camera. On paper, the iPhone 6's 8MP camera should be no match for Z3 Compact's 20.7MP. However the tech behind the iPhone 6's camera has put it ahead, with camera experts DxO labs declaring the iPhone 6's camera to be the best ever on a smartphone at the time of its launch, scoring higher on its benchmarks than the Z3 Compact.
One area where the Xperia Z3 Compact handily beats the iPhone 6 in my opinion is with storage. Whilst the Z3 Compact comes with 16GB internal storage, which is the lowest storage option of the iPhone 6, it at least can be expanded up to 128GB via microSD.
For storing videos, music and photos, this is much more cost effective than going for a larger capacity iPhone 6, though of course you can't install apps on to the microSD, so you're stuck with 16GB.
- Read our in-depth iPhone 6 review
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. Ever since he got an Amiga A500+ for Christmas in 1991, he's loved using (and playing on) computers, and will talk endlessly about how The Secret of Monkey Island is the best game ever made.
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