Review: HTC One X for AT&T
Screen
The One X has a 4.7-inch Super LCD with 1280 x 720 pixels. Yeah, that makes it an HD display, and a bright and colorful one at that. The pixel density is tight enough that picking out individual pixels is difficult. Everything rendered on the display is smooth and free of distracting rough edges. I used the device outside for an entire afternoon and had no problem reading the display in direct sunlight. All the menus, screens, and apps were perfectly visible. It is a really, really good display.
Signal
As expected, the One X for AT&T performed much better than the international version. It was able to connect to the network more consistently and remain connected no matter where I took the phone. Where I live in NJ, but the HSPA+ network is strong and the One X sailed along the digital airwaves. Browsing the web and downloading apps over HSPA+ was very, very quick. The phone never dropped down to EDGE during my time with it. When I tested the device under AT&T's LTE network, speeds jumped through the roof. I routinely saw download speeds reach 15Mbps, with averages coming in around 10Mbps. Uploads were also quick, peaking at 5.7Mbps and averaging 3.4Mbps. The One X didn't drop any calls while I tested it, nor did it miss any.
Sound
Calls sounded fantastic through the One X. The quality of calls was impressive, with warm, present voice tones coming through the earpiece. Interference and noise were minimal. Earpiece volume was also excellent, and can be set loud enough to be heard in most environments. Calls routed to the speakerphone were also very, very good, though I noticed a bit more background noise. Volume was good. The ringers and alert tones were plenty loud, though they fall short of rock concert volumes. You certainly won't miss calls in your own home if you have the ringer cranked up. The vibrate alert was a touch weak for my tastes.
Battery
The AT&T version of the One X packs a dual-core Qualcomm Snapdragon S4 processor at 1.5GHz per core. This chip — and the One X — are amazingly efficient when it comes to power management. If you're worried that the One X - with its 4.7-inch display, thin form factor, and 4G radio - will blast through a full charge in mere minutes, set your mind at ease. This thing is the Energizer Bunny of smartphones. It goes and goes and goes all day long with no problems. Despite having all the radios on, social networks and email updating every few seconds, and lots of time spent with the app store and browser, the One X makes it through an entire day with power to spare.