Both the Xperia XZ2 and the XZ2 Compact have a trendy new extra-tall aspect ratio to boast. It's 18:9, to be exact, which is quickly becoming an industry standard, of sorts. Looking at the XZ2 and it's XZ1 predecessor side by side really makes the difference apparent. The top and bottom chins have seen a significant reduction in size. So much so, in fact, that the bottom speaker has to be hidden away near the very bottom of the bezel. Space constraints could very well be behind the specs reduction in the selfie shooter, as well.
Interestingly enough, even though the XZ2 is a bit narrower than its predecessor at 72mm, that reduction seems to come from the narrower display, rather than the side bezels. Those appear mostly unchanged. We were kind of hoping for a nearly bezeless look, like on the Xperia XA2 pair, but Sony apparently decided to to take the new look to the extreme quite yet.
The same logic mostly applies for the display panels themselves. Both have FullHD+ resolution - nothing really crazy like 4K, yet still a noticeable bump up for the Compact, previously stuck at 720p. Sony also decided to stick to what it knows and go for IPS LCD technology, disproving all the OLED leaks that have been floating around lately.
One major upgrade that did make its way into Sony's flagship display tech is HDR video support. Both phones have 10-bit panels and are certified for the BT.2020 color standard. Frankly, determining how that correlates to other industry standards, like HDR10 video is a bit difficult and needlessly technical.
In practical terms, all that really matters is whether content vendors, like Netflix enable their HDR content for the XZ2 and XZ2 Compact. That remains to be seen. For now, the best way for early adopters to take advantage of the HDR panels is by watching the compatible 4K HDR clips captured by their cameras.
Sony also offers an automatic up-conversion system, as part of its "Advanced X-Reality for mobile" engine. It takes SDR video content and seamlessly tries to up-convert its colors to HDR levels during playback. Our admittedly short experience with the tech yielded mixed, but generally positive results. We will definitely do more testing for the full review, but it seems the effect depends heavily on the quality and type of content you feed into X-Reality.
Circling back to the speakers, both the XZ2 and XZ2 Compact have a stereo setup. On the first inspection, the slimmer front chins suggest that some compromises might be put in place to fit into the size restrictions. Surprisingly, that's not the case. Even though the bottom speaker is tucked away into the frame and the earpiece doubles as the other channel, they sound great and perfectly balanced.
Not only does the stereo output sound as good as ever, but Sony claims that through a combination of hardware and software tweaks, its S-Force Front Surround system is now 20% louder, compared to the Xperia XZ1. Since our ear can only do so much, we'll confirm this claim once we get the full review going.
While on the topic of sound, the Xperia XZ2 has another interesting innovation, called a Dynamic Vibration System. It leverages a special vibration motor, with plenty of fine control and low-frequency actuation to provide haptic feedback, or rather "bass emulation" for audio. This works for music and video, as well as most Android apps and games, provided those don't use some obscure method of producing sound.
The intensity of the effect can be adjusted from an additional slider, alongside the volume one on a per-app basis. It is a rather weird sensation at first, but it could improve certain multimedia experiences once you get used to it.
Sony also claims its new vibration module can improve vibration for notifications, making them more noticeable. Unfortunately, the Dynamic Vibration System is only present on the bigger Xperia XZ2, likely due to size constraints.
Another piece of hardware and functionality missing from the XZ2 Compact is the QI Wireless charging. A real shame as well, since Sony is launching the WCH20 wireless charging dock alongside the XZ2 pair. It delivers 9W of power - the fastest current Qi chargers get. Wireless charging can potentially produce quite a bit of heat so Sony has handled this by a small, very quiet fan inside the charger itself. Its ventilation holes, combined with the overall design of the WCH20 make for a distinctly speaker-like look. Don't be fooled though. Besides the Qi wireless coil, the only other feature of the dock is a detachable mounting base that lets it sit vertically or horizontally to potentially double as a multimedia stand.
As far as major features go, the Qi wireless charging and Dynamic Vibration System are the only two the XZ2 Compact lacks, compared to its bigger sibling. There are a few LTE speed and antenna differences as well, but nothing really major.
As for the rest of the internals, Sony has managed to execute the Compact properly yet again. Both phones are based on the same beastly Snapdragon 845 chipset, with all the cooling hurdles that entail. They also share the same 4GB RAM, plus 64GB ROM setup, 19MP camera and accompanying buffered RAM ISP for slow-motion capture, the same stereo speaker setup. Everything is there and that's no small feat.
Well, the battery had to be cut down a bit from 3180mAh in the XZ2 to 2870mAh in the XZ2 Compact, but that comes rather natural with the overall size reduction.
Wile on the topic of differences, the third and final one between the XZ2 and XZ2 Compact pertains to LTE connectivity. Unlike its bigger sibling, which is theoretically capable of download speeds up to 1.2 Gbps, or Cat.18, the compact has 4CA LTE, Cat.15. The downgrade seems to be related to space limitations and antenna count, but in reality, you will probably never be able to tell the difference. At least not with the services most carriers offer today.
That minor detail aside, both phones are decked-out in the connectivity department. A hybrid dual-SIM solution is standard and so are Dual-band Wi-Fi ac, 4x4 MIMO, GPS and GLONASS, NFC, Bluetooth 5.0 and USB 3.1 Type-C, for quick transfers and OTG usage.