Now let's talk about image quality. We pitted the One X against the current cream of the crop -- the N8, Amaze 4G, iPhone 4S and Galaxy Note (which uses the same module as the Galaxy S II) plus Canon's S95 compact point-and-shoot. The camera landed somewhere in the middle of this star-studded pack, marginally beating the Galaxy Note and iPhone 4S while almost matching the Amaze 4G. Sure, it's not in the same league as the N8 (which rivals the S95 in some cases), but this is one stellar camera, especially when you consider that HTC is not positioning this phone as an imaging-centric device like the Amaze 4G. Low-light performance is particularly impressive thanks to the fast f/2.0 lens and backside-illuminated sensor, which combine to gather a huge amount of light. HDR night shots are truly magical -- no mushrooms required. Still, the software relies on a little too much noise reduction in extreme low-light which results in a noticeable loss of detail, and since there's no assist light, the autofocus often struggles in the dark and requires a few touch-to-focus attempts before getting a lock. Pictures taken in most conditions look fantastic, but looking closely we're longing for a sensor with a wider dynamic range and higher quality lens (yes, the N8's Carl Zeiss optics are hard to beat).

Yes, the proof is in the pudding -- people who care little about aperture and shutter settings will take great photos with the One X.

While color balance is generally top-notch we noticed some issues with the white balance being off at times right after launching the camera -- it rights itself after a few seconds, but it's a problem if you're trying to catch that fleeting moment. Metering is usually accurate, but the lack of exposure lock means that in some instances (like sunsets) we resorted to fiddling with the EV to avoid washing out parts of the shot. Of course, we're being picky here and none of this takes into account ease-of-use, which rivals the experience on the iPhone 4S (and beats it, in terms of speed). Yes, the proof is in the pudding -- people who care little about aperture and shutter settings will take great photos with the One X. The One X captures 1080p video at a silky smooth 30fps with continuous autofocus and stereo audio. Results mostly look sharp and sound clear -- we noticed some faint video compression artifacts (bitrate is 10Mbps) and the automatic gain control reacted a little too quickly to wind noise, but this is nothing to be concerned about in most situations. In contrast with how quickly the camera handles stills, there's about a four-second (!) delay between tapping the on-screen video capture button and the actual start of the recording which means you're likely to miss some firsts if you're not prepared. There's one more neat trick worth mentioning, and that's slow motion. Yes, this shooter is able to record 480p widescreen video (768 x 432 pixels, to be exact) at 60fps for playback at about 24fps -- check out our sample video below.

Performance and battery life

Quad-core phones have arrived. While we've already seen the NVIDIA tech on one of our favorite Android tablets, the One X is our first Tegra 3 smartphone to arrive for testing and it doesn't disappoint. We tried to push the hardware as much as we could and it handled nearly all of our tasks effortlessly. GTA3 loaded effortlessly -- and was fast. Even task-switching couldn't sink the phone, although it does pause to think when you jump between heavier tasks like video and gaming. Browser performance is a revelation too. We couldn't spot any tiling issues as we scrolled at high-speed through the front page of Engadget -- none -- pictures were there before we even got to them. This triumphant real-world performance is backed up by some understandably jaw-dropping benchmark scores, besting even the Transformer Prime in Quadrant and Vellamo performance tests and thrashing the Galaxy Note -- our previous smartphone heavy-lifter -- across the board.

HTC One X HTC One S ASUS Transformer Prime Galaxy Note (int'l) Quadrant (v2) 4,906 5,053 4,018 3,854 Linpack single-thread (MFLOPS) 48.54 103.88 43.35 64.3 Linpack multi-thread (MFLOPS) 150.54 222.22 67.05 95.66 NenaMark2 (fps) 47.6 61.0 46.07 32.8 NenaMark1 (fps) 59.5 60.8 60.07 56.6 Vellamo 1,617 2,452 953 901 SunSpider 9.1 (ms, lower numbers are better) 1,772.5 1,742.5 1,861 2,902

While an AT&T-branded One X is set to arrive carrying LTE (and a SnapDragon S4), this global model features both quad-band EDGE and HSPA+ 42Mbps (2100 / 1900 / 900 / 850MHz). Speed tests on AT&T in the US reached about 6Mbps down and 1.2 Mbps up on HSPA+, and Three and O2 in the UK averaged around 2.2Mbps down and just under 1Mbps up on HSPA. Call quality is good, with the noise-cancelling second mic helping to focus on the voice, although some background static remained on our test calls on several networks. Battery life, however, looks likely to pay the price for this. With brightness set to 50 percent, WiFi on but not connected, the One X's 1,800mAh juicepack managed six hours of continuous video playback -- that's two hours short of its sibling, the One S. Obviously, this sort of activity is likely to use the phone's multiple cores, but we found that Tegra 3's 4-PLUS-1 setup still continues to slurp the battery on very light use -- we didn't notice that extra companion core taking any sort of burden off the phone's power consumption. Checking our battery status, it seems like HTC's Super LCD 2 screen -- perhaps unsurprisingly-- was also to blame for a life span that didn't last a full workday. Update: To clarify, we got 12-plus hours of moderate use out of the One X (that's checking, email and social networks, making a few calls, sending some messages, taking a few pictures, downloading a few apps); your mileage will vary. Keep in mind there are differences between the One X and One S beyond the processor, such as like the radio chipset and the display (4.7-inch vs. 4.3, 720p vs qHD, LCD vs. AMOLED).

Software

The latest version of HTC's proprietary skin, Sense 4, comes on top of Android 4.0.3. But this isn't your father's old version of Sense. In fact, it's a much more refreshing take on a skin that used to be incredibly bogged down by nonsense animations and unnecessary UI elements. Is it stock Ice Cream Sandwich? No, not by a long shot. But what you'll get with the One X's user experience is a pleasant mix of ICS and Sense, both halves somehow finding a way to live together in harmony. That's not to say Sense 4 is a complete and perfect Android skin. But it does a much better job figuring out the spirit of stock Android and truly striving to emulate the OS, instead of throwing Google's designs and inspiration out the window. HTC's goal was to make the new Sense much lighter and less burdensome to the rest of the platform, and we'd say it has largely succeeded. There is so much to discuss in the new Sense that our overview of it became too large to include with the rest of our impressions on the One X. To get the full scoop complete with screenshots and video, visit our incredibly comprehensive Sense 4 review.

Wrap-up

There's absolutely no doubt that the One X is a masterpiece of an Android device: it obliterates pretty much all of its competitors by giving even the mighty Galaxy Nexus a run for its money. HTC's really crafted something special here, with a brilliant combination of branding, industrial design and user experience. This handset looks and feels stunning, with top-notch materials and build quality, the most gorgeous display we've ever stared at on a phone, a fantastic camera that's fast and easy to use and a laundry list of every possible spec under the sun. Sense 4 is thin and light enough to enhance -- not detract from -- stock Ice Cream Sandwich. Pinch us, 'cause frankly, we're smitten.

Ultimately, buying a One X is a lot like getting a unicorn -- it's wild, fast, white, beautiful, expensive and fickle.

Still it's not all rainbows and glitter. While it's incredibly quick and smooth in actual use, we're surprised that the quad-core Tegra 3 in the One X performed slightly worse in our benchmarks than the dual-core Snapdragon S4 in the One S. Battery life is by far our biggest concern and we really hope that HTC addresses this head-on with future software updates. It'll be interesting to see how its LTE equipped twin (which is also Snapdragon S4-based) fares in those areas when it launches in the next few weeks -- let's just hope AT&T keeps the firmware as unadulterated as possible. Ultimately, buying a One X is a lot like getting a unicorn -- it's wild, fast, white, beautiful, expensive and fickle. Time will tell if dressage school tames this power hungry beast. Mat Smith, Brad Molen and Richard Lai contributed to this review.