It's immediately apparent the Xperia Z3 doesn't carry quite the bulk of the Z2, being thinner, lighter and just as simply designed. There's nothing much to the glass front and back of the device (which comes in white, black, silver-green and copper colors), with camera lenses, bezels and understated logos more or less where you'd expect them. The aluminum power key, volume rockers and dedicated camera shutter button adorn the right edge of the device, alongside the waterproofing flaps that hide the microSD and SIM card slots. One more noticeable difference from the Z2 is that the aluminum edges are now broken up at the corners, and replaced with corner caps made out of a type of nylon. These are more resilient than the aluminum, we're told, and thus won't ding or deform if you happen to drop the thing.
Otherwise, not much has changed on the design front at all. The Z3 does have a higher waterproof and dustproof rating than the Z2, even if you can't tell, at IP65/68. Sony has stuck with a 5.2-inch, 1080p display on the Z3 (just like the Z2), although this panel has contrast-enhancing technology for improved sunlight readability. Sony didn't want to upgrade to a 4K or even 2K display for a better spec sheet if it was going to impact battery life, thus no improvement in resolution. The display also has dedicated memory, so it won't refresh when it doesn't have to, saving on battery life further. The more efficient Snapdragon 801 should help on that front, too, and every little bit helps when you have a 3,100mAh battery (100mAh less than the Z2) driving such a powerhouse. We're told that it'll last for two days without needing to be plugged in, but we'll have to see what kind of usage conditions that entails.
The camera hasn't changed in terms of megapixel count from the Z2. The 20.7-megapixel sensor, however, is said to have better low-light performance, a new 25mm wide-angle G-lens and a new upper limit to the ISO setting of 12,800 (a smartphone first, apparently). A new "Intelligent Active Mode" when shooting video offers improved digital stabilization, which operates on top of the Steadyshot tech Sony already incorporates into its top-end devices. New camera features include live-to-YouTube streaming and "Face in," a mode that captures feeds from both the rear and 2-megapixel front-facing camera simultaneously. There's also "AR fun," which lets you add 3D AR effects to the frame, and a multi-camera mode that pairs the Z3 with other Sony cameras and smartphones via WiFi Direct, allowing you to see both viewfinders on the screen and dynamically direct video from just the one phone.
The Z3 is also equipped with high-resolution audio playback, and an upscaling engine called DSEE HX that upscales low-res audio (whether that be from streaming services or files) to near hi-res audio, although you'll need a high-end set of headphones to feel the benefit. Finally, Sony has equipped the Z3 and others devices in the Z3 family with PlayStation 4 Remote Play, previously only a feature of the hand-held PlayStation Vita console. It works best over your home WiFi network (say, if the TV is required for some other purpose), but it can theoretically work anywhere, albeit with terrible lag. A new controller mount that adds a suction cup to the DualShock 4 controller gives you the optimum setup for smartphone gaming. The Remote Play feature isn't due to be enabled until November, however, possibly a little later than the Z3's "fall" release date for an as-yet unknown price.
For one reason or another, Sony hasn't had the best relationship with carriers in the US. Whether that be because of a lack of interest from them, or because Sony prioritizes other markets, the winds of change are upon us. T-Mobile has already confirmed it'll be ranging the Xperia Z3 at launch, making the best Sony has to offer available on (hopefully) reasonably priced payment plans, where interested consumers otherwise have to source unlocked models at exclusionary prices.