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Asus PadFone X (AT&T) review: Unique two-in-one hybrid proves to be more than a gimmick

The PadFone X is a quad-core handset that docks itself into a fully functioning 9-inch tablet. Useful? Yes. Weird? Perhaps. But just don't call it a party trick.

Lynn La Senior Editor / Reviews - Phones
Lynn La covers mobile reviews and news. She previously wrote for The Sacramento Bee, Macworld and The Global Post.
Lynn La
11 min read

Other than its predecessors , there's nothing quite like the Asus PadFone X. As a smartphone-tablet (and sometimes even laptop!) hybrid, it is an amalgamation of two devices aiming to give users the most seamless and efficient mobile experience.


Asus PadFone X (AT&T)

The Good

AT&T's Asus PadFone X has a fast quad-core processor, a capable 13-megapixel camera, and it can dock into a 9-inch tablet that doubles as a charger.

The Bad

When combined, the PadFone X has a clunky design and its rear-camera loses a few some of its features. The device also comes with a lot of bloatware and a nonremovable battery.

The Bottom Line

Though it has last year's specs, the PadFone X marries two mobile devices into one convenient form at an affordable price.

When I first looked at it, the skeptic in me remained unconvinced. It's too clunky. It bulges in the back. And at $200 on-contract (or $550 without), it seemed better to invest in a single top-tier tablet or handset, rather than settle for two mediocre-looking devices.

After spending time with it, though, I stand corrected. First, the phone in and of itself is solid and reliable. You can't go wrong with its sharp 1080p screen, swift quad-core processor, and nimble 13-megapixel camera. But once it's plugged into its dock, consuming media and browsing the Web take on the more immersive form that only a bigger tablet-size screen can deliver -- all without forming a disconnect in your ecosystem.

Does the PadFone X achieve full cross-device zen? With its current design aesthetic, not just yet. But for those struggling between the land of the smartphone and the land of the tablet, its price is right for two devices, even if the specs run similar to the flagships of last year.

The device of many hats: Asus PadFone X (pictures)

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Measuring 5.7 inches tall and 2.9 inches wide, the handset is comfortable to hold, and easy to maneuver with one hand. It sports tapered edges with a brushed-aluminum design that adds just a dash of style to the otherwise bland-looking device. However, at 0.4 inch thick and weighing 5.3 ounces, it's a tad heftier than most high-end 5-inch phones.

On the top edge is a 3.5mm headphone jack, and to the right are a sleep/power button and a volume rocker. At the bottom is a Micro-USB port flanked by two circular ports, which are used for plugging into the tablet dock. Located on the back is a 13-megapixel lens with accompanying flash, and a barely-there speaker grille right below it.

The handset features a sharp, 5-inch 1080p display. Josh Miller/CNET

To access the microSD card slot that accepts cards of capacities up to 64GB, you'll need to pry the battery door off using the Micro-USB opening at the bottom. This requires more muscle than it should, and my fingers and nails had to struggle to get through the task. When's all said and done, you can expand your storage on the right of the handset and view the nonremovable 2,300mAh battery.

The phone has a 5-inch display with a 1,920x1,080-pixel resolution. The touchscreen is sharp and responsive to the touch, but it can look a tad dim. This was most apparent when viewing a plain swatch of white; it doesn't affect the overall viewing experience, but it is something I noticed immediately.

But even as unexciting as the phone's design is, the whole aesthetic looks even worse when plugged into the tablet. For one thing, the tablet (which measures 9.9 inches wide, 6.8 inches tall, and 0.8 inch thick at its thickest point) will end up bulging out the rear. That means when placed face-up on a tabletop, the tablet will never sit flat. And for a 9-inch display, it's heavy. It'll weigh 23.4 ounces combined, compared with the 13.1-ounce Amazon Kindle Fire HDX 8.9 and the 16.5-ounce Sony Xperia Z2 Tablet .

The tablet's dual front-facing speakers. Josh Miller/CNET

To connect the two, you'll need to slide the handset, screen-side down, against the back of the tablet. A short haptic vibration will let you know that it's fully docked, and ridges on the side of the tablet's canal locks the phone in place. Indeed, while carrying it around, it felt very snug and secure. When I held it upside down in attempts to shake the handset loose, I didn't succeed.

The station dock cannot function without the handset, so only when it is inserted can you begin using the tablet. The tablet has a 1,920x1,200-pixel resolution, which is passable, but not as crisp as the phone's (in case you're curious, the pixel per inch count will drop from 441ppi to just 252ppi on the tablet). However, due to its 9-inch size, watching videos and playing games will be much more comfortable and compelling. The device also has dual front-facing speakers on either side of its bezel, making audio loud and clear.

Software features

The PadFone X runs Android 4.4.2 KitKat and comes loaded with the usual array of Google services like the Chrome browser, Drive, Gmail, Search (including voice), Plus, and Photos. There's also Hangouts, Maps, the Play app store and its corresponding Books, Games, Movies and TV, Music, and Newsstand portals, and YouTube.

Overlaid on top is Asus' ZenUI interface. Featuring brightly colored, flat icons, and boxy, oversize widgets, the skin is user-friendly, but it can come off as too playful and unsophisticated to the austere eye. Personally, I like it. The blue notifications shade is easy to read, and the circular settings icons from the pull-down menu are pleasingly minimalistic.

Some apps that reflect and continue this ZenUI are the calendar app, the SuperNote memo app, and the to-do Task list. Asus threw in usage and file managers; Splendid, which adjusts your displays color hues; and the photo organizer, Story, as well.

The notifications shade (left) and the pull-down settings menu from Asus' ZenUI interface. Lynn La/CNET

When it comes to moving in between your handset and your tablet, downloaded apps will display on both components. Certain customization settings, like wallpapers and widgets, will have to be settled independently from each other. Others, though, affect both -- turning on and off auto-rotation, for example, is one of these cross settings. If you have 4G LTE on your phone, you'll also have it on your tablet, and you can make calls on either devices.

AT&T preloaded a hefty amount of its own bloatware. There's FamilyMap, which helps you locate family members on your AT&T account; 5GB of free cloud storage through AT&T Locker; and if your device gets stolen or lost, Mobile Locate will pinpoint its location. The carrier preloaded apps to help setup and use your handset , as well as your visual voice mail.

Other apps include the AT&T Digital Life home security service; MyAT&T, which lets you check your data and account info; and an app called AT&T Smart Wi-Fi that connects your phone to publicly available Wi-Fi. Finally, there is DriveMode. This sends a customizable message to incoming calls or texts when it senses the device is traveling faster than 25 mph.

Asus' ZenUI in all its tablet, landscape-oriented goodness. Lynn La/CNET

Third-party goodies include Amazon Kindle; an app that adjusts audio settings depending on what you're listening to; Beats' music streaming service; a mirror app that utilizes the front-facing camera solely as a reflection; and Famingo. Famingo enables users to set parental controls and download kid-friendly games and videos. There's the WildTangent games portal; Isis Wallet's digital payment system; the Lookout security app; a password organizers called Keeper; a movie editor, the mobile office suite Polaris Office 5; a battery and power manager; Facebook; and the YellowPages.

Basic task management apps are native Web and email clients; a calculator; a clock with alarm functions; a sound recorder, and a weather app. All this adds up to lots of preloaded software -- that you can't always get rid of, mind you -- running on 16GB of listed internal storage and 2GB of RAM.

Camera and video

Photo quality for the 13-megapixel camera was solid. Pictures did tend to have a noticeable amount of digital noise, both in dimly and well-lit environments. In addition, light sources and white hues were often blown out and overexposed. Aside from that, however, photos were sharp with well-defined edges. Colors looked true-to-life and white balance was accurate.

The camera shutter is fast as well; auto- and touch-focus adjusted quickly and I didn't notice any lag between my moving of the camera and the viewfinder feedback. To learn more about these photos, click on them below to view them at their full resolution.

In this outdoor photo taken on a cloudy San Francisco day, you can see how the sun's reflections on the stone cubes to the left are overexposed. Lynn La/CNET

Notice on the left grey wall and against the carpet there is a notable amount of digital noise in this well-lit indoor picture. Lynn La/CNET

This closeup picture is focused correctly, and shows how vibrant these orchid petals are. Lynn La/CNET

In our standard studio shot, objects look sharp but the white background and color swatches look grainy. Lynn La/CNET

Video quality was on par with the camera. While shooting in 1080p HD video, recordings were smooth and sharp. Both moving and still objects remained in focus, colors were accurate, and lighting and contrast adjusted appropriately quick as I moved the camera around. Nearby and general audio picked up well too. Recording 4K video, however, fared worse in comparison. The frame-rate was slower and recordings looked choppier.

With the handset alone, the 13-megapixel rear lens has plenty of editing options. Alongside digital zoom, a flash, a timer, face detection, and gridlines, users will get nine shooting modes. These include HDR; smart remove (where you can edit out unwanted objects or people; all smiles, which lets you pick-and-choose the best facial expression out of five shots; and even a GIF animation tool.

You can take pictures in five sizes (ranging from 3,264x2,448- to 4,160x3,120-pixel resolution). There are also nine Instagram-esque filters, five white balances, ISO and exposure meters, burst shot, three focus options, and a special setting for low-light environments. The video camera can shoot in five sizes (from MMS all the way up to 4K video), record time-lapse movies, record in both slow- and fast-motion, and take pictures while shooting.

Understandably, the smartphone's 2-megapixel front-facing camera has less options. It only has seven shooting modes, two picture sizes (from 1,600x900- to 1,600x1,200-pixel resolution), and three video sizes (from MMS to 720p). Plus, some video modes, and the tools for focus and low-light have been stripped.

Depending on whether or not the device is docked, this camera ranges from a 5.5- to a 13-megapixel lens. Josh Miller/CNET

When you plug the PadFone X into its tablet component, the camera options are whittled down even more -- despite it being essentially the same rear-shooter. It now maxes out as a 5.5-megapixel lens and can shoot up to 720p video. A few shooting modes and filters are eliminated, and all video modes are eliminated.

With the tablet's 1-megapixel front-facing shooter, you'll get the bare bones of all these options. There is only one shooting mode (a tool called "beautification" that adjusts skin tone and softness), just three Instragam-like filters, one picture size, and recording drops all the way to 420p. Interestingly enough, however, while all video modes have been erased with the rear-facing camera when the device is docked, recording a timelapse video has somehow stayed an option for this 1-megapixel camera.


Call quality and data speeds

I tested the quad-band (850/900/1,800/1,900) PadFone X in our San Francisco offices and call quality was good, with a few hiccups. For instance, my calling partner's voice sounded scratchy at times, and during times of absolute silence, I did once hear a subtle whooshing sound that went away quickly. All in all though, call quality was adequate. None of my calls dropped, audio remained continuous, and volume range was adequately loud. I could hear my calling partner well, and she was easy to understand.


Audio speaker quality on both devices fared worse, unfortunately. Though loud and easy to hear, voices came off harsh and tinny, and while my partner sounded slightly better on the tablet's dual front-facing speakers, audio still sounded hollow. Likewise, I was told that my voice on speaker was weak on the other end of the line. Despite being nearby, she described my voice as if I were in a large office meeting using an intercom speaker.

As for the handset's 4G LTE connectivity, data speeds were fast but inconsistent at times. Certain websites, for example, would load in just a couple of seconds during one trial, and then take three or four times longer the next, after initially stalling for several seconds.

On average, however, it took 5 and 16 seconds to load CNET's mobile and desktop sites, respectively. The New York Times' mobile page finished loading after 6 seconds and its desktop version loaded in 5. The mobile site for ESPN clocked in at 3 seconds and 6 seconds passed for the full Web page. After five trials, Ookla's speed test app averaged out with a rate of 27.92Mbps down and 10.63Mbps up. Lastly, the 48.61MB game Temple Run 2 usually finished downloading and installing in 34 seconds.

Asus PadFone X (AT&T) Performance Times

Average 4G LTE download speed 27.92Mbps
Average 4G LTE upload speed 10.63Mbps
Temple Run 2 app download (48.61MB) 34 seconds
CNET mobile site load 5 seconds
CNET desktop site load 16 seconds
Restart time 33 seconds
Camera boot time 1.33 seconds

Processor and battery

Inside the phone is a 2.3GHz quad-core Snapdragon 800 processor. Whether it was plugged into the tablet or used by itself, simple but necessary tasks -- like calling up the keyboard, browsing through the app drawer, and returning to the home screen -- were executed swiftly and without any problems.

Playing the graphics-intensive game Riptide GP 2 also proved to be a smooth experience. The app never force quit or stuttered, and high-frame rates rendered polished images and fluid animations. You will, however, have to wait when you dock and undock the handset to use either components. This usually lasts less than a second, but that brief pause in usability is noticeable nonetheless.

A few of the phone's Ookla speed test results (left) and its highest Quadrant score. Lynn La/CNET

On average, the device took 33 seconds to restart itself and 1.33 to launch the camera. Benchmark tests revealed its best Quadrant score to be 21,723, and its best multithread Linpack result was 705.718 MFLOPs in 0.24 seconds. This puts it in a respectable but lower level against current flagships like the Samsung Galaxy S5 , HTC One M8 , and LG G3 . (Handsets like these have Quadrant scores between 23,000 and 24,000.) Instead, the PadFone X is closer to marquee handsets from last year, like the LG G2 , which score at the 19,050 mark.

In addition, I put the PadFone X through our ringer for tablet testing, and its Krait 400 CPU and 550MHz Adreno 300 GPU showed impressive benchmark results. On average, it loaded the first level of N.O.V.A 3 in 31 seconds, and its 3D Mark scores edged out other impressive devices of similar size and caliber like the Amazon Kindle Fire HDX (8.9) , the Sony Xperia Z2 , and (understandably) its September 2013 predecessor . Click here to read more about how the 3D Mark benchmark test works.

3DMark scores (Unlimited)

Asus PadFone X 19298 20161 16782Amazon Kindle Fire HDX (8.9) 12858 12163 16074Sony Xperia Z2 tablet 18971 19642 16944Asus PadFone (Sept. 2013) 17457 17763 16463
  • Overall Ice Storm Score
  • Graphics Score
  • Physics Score
Note: Longer bars indicate better performance

3DMark test breakdown (Unlimited)

Asus PadFone X 109.8 73 53.3Amazon Kindle Fire HDX (8.9) 58.7 48.1 51Sony Xperia Z2 tablet 102.4 73.2 53.8Asus PadFone (Sept. 2013) 90.9 67.2 52.3
  • Graphics Test 1
  • Graphics Test 2
  • Physics Test
Note: Longer bars indicate better performance

Unfortunately, anectodal observation for the handset's 2,300mAh battery has been unimpressive so far. Even with mild usage, its battery would drain about 10 percent every hour. True, the screen's brightness was on maximum, but that rate was still too fast. After four or five hours, the battery was already in the red and needed a charge. You can charge the phone with the tablet's own 4,990mAh battery, which will increase the reported talk time from 20 to 54 hours.

During our battery drain test for continuous video playback, the phone itself lasted 8.45 hours. When we carried out our battery drain test for the handset and the tablet together, video streaming lasted longer at 9.2 hours. According to FCC radiation measurements, the phone has a SAR rating of 0.98W/kg.

Who should buy this?

If you're in want of top-of-the-line specs from either your smartphone or your tablet, you won't find it in the Asus PadFone X. For those looking for a high-end handset, you'll find the specs falling behind current flagships, and the tablet component superfluous. For $200 with contract, it's best then to go ahead and get a current marquee smartphone. You can also get a flagship from last year, like the Samsung Galaxy S4 or LG G2 . Sure, they might be "old," but the specs are on par with the PadFone X and they're $100 cheaper.

Likewise, compared with premium tablets like the Samsung Galaxy Tab Pro 10.1 , the device's lack of an ultra-sharp display and productivity framework won't satisfy someone who wants to be on the bleeding edge of tablet technology.

The PadFone X shapeshifts to suit your needs. Josh Miller/CNET

But bundled together at this price, the PadFone X is best for those who want both a smartphone and a tablet on a tight budget. True, the combo doesn't have the most aesthetically pleasing design, but what you lose in style, you'll gain other benefits elsewhere. Not only will you get a larger, more inviting display, you also won't have to sacrifice performance or deal with any platform inconsistencies.

Best of all, the PadFone X will adapt to your priorities. It'll be your smartphone for your everyday use, a tablet over the long weekend full of Netflixing, and with its $100 keyboard accessory, it can be your laptop for the week while you're off traveling for work. Ultimately, it's an affordable shapeshifter that'll be what you need, when you need it.


Asus PadFone X (AT&T)

Score Breakdown

Design 7Features 8Performance 7