Asus PadFone X (AT&T) review:

Unique two-in-one hybrid proves to be more than a gimmick

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.

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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.

Asus PadFone X (AT&T) call quality sample

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.

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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
Amazon Kindle Fire HDX (8.9)
Sony Xperia Z2 tablet
Asus PadFone (Sept. 2013)


Overall Ice Storm Score
Graphics Score
Physics Score


Longer bars indicate better performance

3DMark test breakdown (Unlimited)

Asus PadFone X
Sony Xperia Z2 tablet
Asus PadFone (Sept. 2013)


Graphics Test 1
Graphics Test 2
Physics Test


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.

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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.

What you'll pay

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