The sad truth of the Padfone is that the phone itself -- quite literally the brains of the operation -- is the most attractive thing about it. Why's that sad? Because its design is dull to the point of inducing ennui. That's a shame too, especially considering this newer, faster version of the Padfone doesn't look nearly as handsome as last year's model, the Padfone Infinity. Your taste may differ, but the Infinity featured cleaner lines and a handsome brushed-metal finish that stands in stark contrast to all the bland, dark, chintzy-feeling plastic featured on the X.
So yes, the Padfone X isn't what you'd call a looker. The sole standout here is the 5-inch 1080p display. As you'd expect, the speaker and front-facing, 2-megapixel camera sit just above that satisfying screen, while a shiny ASUS logo greets you from below. Taking a little tour around the rest of the phone yields precious few surprises: You've got the sleep/wake button and volume rocker nestled on the phone's right edge. In fact, the only real hints that the Padfone aspires to something bigger (literally) are two holes on the phone's bottom, on either side of the micro-USB port. They're meant to anchor the phone firmly into the Padfone Station, the beefy exoskeleton that converts 'fone to pad.

That's not to say the Padfone X is completely bland, though. Peer a little closer and you'll see its removable backplate is flecked with tiny silver specks. It's perhaps the most minute concession to style I've ever seen on a phone, if only because the effect is so subtle you'll outright miss it most of the time. The rest of the X's rear isn't nearly as subdued -- a 13-megapixel rear camera lives just left of center, with the LED flash and speaker grille sitting to the east and south of it, respectively. Once those are out of the picture, all that's left to capture your eye are AT&T and Padfone logos emblazoned prominently on the back. Assuming you manage to pry off that rear plate, you'll find the microSD reader (which was notably absent in last year's model) and microSIM card slot parked next to a 2,300mAh battery.
Thankfully, that old cliché holds true here: It's what's inside that counts. In this case, "what's inside" is one of Qualcomm's 2.3GHz quad-core Snapdragon 800 chips along with 2GB of RAM -- a combination that runs the show admirably. Alas, things get considerably less charming when you dock the device into the Padfone Station. The frame the phone slides into is an unwieldy, chunky thing that creaks and groans even when you apply light pressure to it. And those bezels? Oh my. There's close to a full inch of black nothingness bounding that 9-inch display on all sides, which only serves to make the tablet look like a cheap digital picture frame from holidays long past. In fairness, the bezels aren't all bad -- they provide plenty of room for meaty thumbs to rest, and they house a pair of (sadly lacking) front-facing speakers.

The back of the tablet dock is swathed in the same silver-flecked plastic as the phone, but there's no way you'll notice that before you spot that gaping maw where the Padfone is meant to slot in. It's impossible to screw up the process: The Padfone slides in with its screen facing inward, and once in place, it'll start sipping on a larger 4,990mAh reserve battery. You're also left with a tablet that has a very conspicuous hump on its rear, but at least the edges of that hump provide a place for your fingers to sit when you're grasping the tablet with both hands. This does make holding the Padfone vertically just a little awkward, though it's hardly a dealbreaker.
Oh, and if you're really into the idea of the Padfone as a true all-in-one machine, you can pick up a specially designed Bluetooth keyboard to go with it. It makes the combined device much heavier thanks to a sizable built-in battery (which can't be used to charge the tablet, unfortunately), and the dearth of space ASUS had to work with made for some frustrating design decisions. Consider the layout: It's about as cramped as you'd expect a keyboard this size to be, and certain critical keys like the apostrophe are only accessible by way of the Function key. That's not to say it's all bad, though. The trackpad? An absolute joy to click. You'll also get days of use out of the thing, though whether or not you'll want to is another story entirely. Trust us: Pass on this unless you're absolutely desperate.
Display and sound

ASUS' designers may have been half-asleep when they crafted the Padfone X, but someone along the line made sure it at least got a solid pair of screens. Ironically enough, it's the smaller display that shines the brightest here -- the 5-inch 1080p panel is the crisper of the two since it packs nearly twice as many pixels per inch as the tablet's screen does (449 ppi versus 214, if you're curious). Colors on both the big and small displays are vibrant and have just the right amount of pop -- no seared retinas here, thanks very much. A preloaded app called "Splendid" lets you muck around with color hue, saturation and balance in case you've got some especially persnickety eyes. Viewing angles are more than respectable, too, with hardly any color distortion even when you peer in from the most awkward angles. My only real niggle is that maximum brightness for both screens is lacking once you take the Padfone outdoors.

Considering the whole point of buying a Padfone X is to have a hot-swappable duo of displays, ASUS gets kudos for not skimping on those Super IPS+ LCD panels. That said, it's earned itself a few demerits for some depressing speaker quality. The phone itself has just the one largely wimpy speaker on its back, and the lackluster sound it puts out is right in line with my low expectations. You'd think that with a pair of front-facing speakers, the Padfone X's tablet form would be able to pump out jams with at least a little more panache. Not so, sadly. My usual suite of test tracks sounded airy and insubstantial through those drivers; the mids and highs of Sutton Foster's jaunty crooning were well-rendered, but there was a distinct lack of support in the low end that left me wanting much more. Trust me: You'll want to run your collection of drum n' bass tracks through a pair of headphones instead.
Or maybe you shouldn't, since the review unit ASUS provided me occasionally did something a little ridiculous. You see, when you're playing music or watching a movie with the Padfone docked in tablet mode, the audio gets routed through the Station's two front-facing speakers. Makes sense, no? One time, though, when I plugged headphones into the proper jack, I heard audio through the headphones... and through the phone's rear speaker. So much for privacy. To be fair, it hasn't happened since, but I've reached out to AT&T anyway for comment. I'll update this review if I learn more. For now, it's possible the issue had something to do with the fact that I was testing a pre-production (read: not-final) unit.
Software

With the Padfone being as downright kooky as it is, it's a bit surprising to see how little ASUS fiddled with Android 4.4.2. There are splashes of paint here and there -- a rejiggered launcher that lets you sort and hide apps, a circle-heavy notification shade that looks like it came from the Galaxy S5, a slightly cramped default keyboard -- but they never completely obscure the rich flavor of KitKat that lurks below the surface.
Seems like AT&T was more than happy to pick up where ASUS left off. You guessed it: The Padfone X is just packed to the gills with AT&T bloatware, from account-management apps to game portals like WildTangent to Beats Music. If you're anything like me, your blood pressure starts to rise at the first sign of carrier intrusion -- thankfully that cruft can be easily uninstalled from the device's settings. In fact, you don't even need to go that far if all you want is to remove the offending apps from your sight.