Sony has come a long way in the past couple of years, turning into a highly focused company that relies on exquisite design to differentiate its products.
The Xperia Z, released in early 2013, was Sony's comeback announcement, but the Xperia Z1 is the phone that really positions Sony as a top phone maker. At first glance, the differences between the Z and the Z1 are not that substantial, especially if you don't follow Sony closely. But the two phones are distinct in many aspects that we will go through in our Xperia Z1 vs Xperia Z comparison.
We take a look at all the things that matter, from the industrial design, to the display, specifications, and software. Let's dive in.
Design and build quality
The Z1 is an evolutionary upgrade over the Xperia Z, sharing all the design traits that Sony has used throughout its product lineup this year. Some users might even confuse one device for the other, though the bigger footprint gives the Z1 away, once you put them side by side.
The Sony Xperia Z was among the first devices to feature the OmniBalance design philosophy, which entails a minimalist, symmetrical, and angular aspect, highlighted with metallic accents, such as the now iconic silver power button. The Z is also resistant to water and dust, thanks to the plastic flaps that cover its ports. They might not be an elegant solution, but the flaps are durable and they get the job done. For a phone of its size, the Xperia Z is reasonably lightweight and easy to handle.
In the opposite corner, the Xperia Z1 feels like a more mature version of the Z, that is not only larger and heftier, but also more refined in terms of design. Featuring a metal frame instead of the plastic on the Z, but the same slate look, the Xperia Z1 feels sleeker and more solid than its older brother. The heft gives it a premium feel, but it may also make it unwieldy for some users. This is a large and heavy phone, but its handling is slightly improved by the subtle curvature of its metallic frame, which makes it nicer to hold. The buttons are in the same position as on the Xperia Z, but the Z1 gains a two-stage camera button, which is important for a phone whose main selling point is the high-quality camera.
To wrap up, the Xperia Z1 is definitely the more refined device, but the Xperia Z is not a clunky phone by any means.
Display
Right of the bat, you'll notice the rather large bezels surrounding the displays of both screens. The slimmer bezels on some competing devices make Sony's phones look a bit dated, but that probably won't matter for many customers.
The Xperia Z's Full HD screen is very crisp, at 441 ppi, and looks great head on, though the image quality plummets when you look at the phone from an angle. It's one of the phone's biggest downsides, though some people are not that bothered by it.
On the Xperia Z1, Sony kept the same general characteristics – 5-inch, Full HD, TFT LCD – but improved the general quality of the image and the viewing angles. The difference is immediately visible when you put the two phones side by side – the black on the Xperia Z1 is deeper and colors are more intense, thanks to the use of Triluminos, a technology that enables LCD screens to display a richer color gamut.
The viewing angles are still not as good as they could be on the Xperia Z1, but they are certainly better than on its predecessor. Then, there's the minor problem of the LCD backlight bleeding around the panel's edges. These qualms aside, the Sony Xperia Z1's display is beautiful and the dark tones of Timescape UI really complement it.
Hardware and performance
Back when the Xperia Z was released, some have criticized Sony for opting for a processor that was already on its way out, the Snapdragon S4 Pro. Clocked at 1.5GHz and packing an Adreno 320 GPU, the S4 Pro processor does its job satisfactorily, helped in part by the modest requirements of the mostly bloat-free Timescape UI. Overall, the Xperia Z is a decently performing phone, but it's nowhere nearly as future-proof as the new Z1.
Swapping the S4 Pro for the latest and greatest from Qualcomm, the Snapdragon 800, greatly improves the smoothness of the Xperia Z1. You get faster clock speeds and a new and improved GPU in the Adreno 330, and the immediate result is the lag-free operation of the Z1. Everything is silky smooth, from the user interface to the apps, except for a few cases when background operations seem to cause delays, though that's not Sony's fault. Looking forward, the Snapdragon 800 will keep the Xperia Z1 performing adequately for at least a couple of years.
Besides the different processors, the Xperia Z1 and the Xperia Z feature mostly the same hardware. One big difference is the larger battery on the Z1 (3000 mAh vs 2300 mAh), which can take you through a full day of work without breaking a sweat. Disappointingly, Sony chose not to equip either of these devices with features that made it to other devices in its lineup, such as the ability to use various objects as a stylus, which we liked on the Xperia Z Ultra.
Camera
Until now, the Xperia Z1 proved superior to the Xperia Z, but never dramatically so. That changes with the camera, which is great on the new Z1, compared to the nice-but-not-great shooter on the Z.
To be clear, the Xperia Z's 13MP camera is not a bad performer, but it's not something to praise as a defining feature either. It takes decent images, and Sony's well-known Superior Mode is great for those who don't like to fiddle with settings to get a nice picture. The manual mode unlocks a few more options, but the Z's camera app is generally simplistic. The areas where picture quality lags behind are low-light image taking and color reproduction, which is off in some cases.
Sony invested a lot of time and resources in perfecting the camera software and hardware on the Xperia Z1, starting with the 20.7MP sensor. The sensor is larger than on most smartphone cameras, but it's not just about the size. The picture quality and color reproduction are improved compared to the Z, and any shot that benefits from good light is almost guaranteed to turn out great. Low light shots are pretty good too, but we think the noise reduction algorithm reduces too much detail from darker spots.
There are some issues though – one is the fact that you can only use the 16:9 format at a resolution of 8MP, which is a shame. Then there's the slight smudgy look of areas that are outside the focal point, that makes poorly focused images even more unattractive.
Sony spruced up the camera app a bit with add-on support and some new features, such as the ability to post an image directly to Facebook.
Software
Because Sony didn't make major changes between the two generations, there isn't much to say about the software differences between the Xperia Z1 and the Xperia Z. You get the same clean, minimalist interface on both phones, and the user experience in basically the same.
Unlike some competitors, Sony remained close to the stock roots of Android, and the changes it did operate are unobtrusive. Of course, Sony's media apps such as Walkman are front and center, but they don't get in the way if you don't like them. Small Apps, simple apps that you can open as overlays on the screen, give you a basic level of multitasking, a nice addition to stock Android.
Price
Sony currently focuses on Asia and Europe as its main markets, and for this reason, the availability of the Xperia Z and Z1 in the United States is limited. Currently, you can acquire the Xperia Z from T-Mobile for $20 a month on a two-year agreement. Unlocked, the phone can be yours for a reasonable $500.
As of this writing, the Xperia Z1 hasn't been announced on any US carrier, though it's possible that T-Mobile will pick it up. The Z1 can be had for $700 unlocked, from Sony or from specialized retailers.
More Xperia Z1 video coverage
Final thoughts
Choosing between the Xperia Z1 and the Xperia Z shouldn't be too hard in theory. The Z1 is generally a better version of the Xperia Z, and thus delivers improvements and refinements across the board. The processing power is superior, the design is more polished, the display is better, and the camera is a marked improvement. However, the Z1 is not able to fully escape the problems that bogged down its predecessor. The display still has a slight problem with the viewing angles and the camera is still delivering inconsistent image quality.
There are two factors that might push you towards the Xperia Z: its smaller size and its smaller price. But if money is no problem for you and you don't mind the extra heft, the Xperia Z1 emerges as the clear winner.
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