Measuring up: The Xperia Z3 (left) and Z3 Compact (right)
The Z3 and Z3 Compact both come with 16GB of internal storage -- less than the Z3v's 32GB -- and an SD card slot for external storage expansion. (If you buy the Z3 from T-Mobile, that specific version of the phone has been upgraded to include 32GB of internal space as well.) That aside, the only important under-the-hood difference between them and the Verizon model is that the Z3v supports wireless charging while these devices do not. That's a bummer, as the waterproof nature of the phones means their charging ports are protected by small flaps you have to pull off every time you want to plug them in -- which is a minor pain in the putoodle. Sony does offer a proprietary charging dock if you feel like ponying up an extra 27 bucks to get around the inconvenience -- not an ideal solution, but it's something.
As for the software -- well, it's okay. Decent but not exemplary; better than what you'll get on most manufacturers' devices but not as good as what you'll see from the likes of Google, Motorola, or even HTC. Especially with the Android 5.0 Lollipop release out in the wild, going back to a needlessly skinned 4.4 setup feels like a step in the wrong direction. (Sony has said it'll upgrade the phone to Lollipop, but the timing is vague -- and the company hasn't exactly been the speediest at delivering rollouts in the past. We also don't know to what extent Sony might modify Google's excellent new user interface before sending it out to its phones.)
There's not a heck of a lot I can say about the software that I didn't already address in my coverage of the Xperia Z3v, so I'll refer you there for the full nitty-gritty. In short, Sony definitely makes its share of arbitrary changes to the UI that range from mildly annoying to sigh-inducing -- like the abundance of bloat and the way-too-prominent pushing of its own storefronts throughout the OS. But for the most part, it's not too bad. It's really all relative; given the choice between Sony's software or Samsung's or LG's, I'd take Sony's every time.
(Update: A software update sent out on November 21st removed the most prominent and obnoxious link to Sony's storefront from the Z3 devices. Progress!)
On the plus side, it's worth noting that both the Z3 and Z3 Compact are able to stream and play PlayStation 4 games from a console connected to the same network. If gaming is your thing, that's a valuable perk you won't find anywhere else (outside of the Xperia product line).
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