The One X can connect to AT&T's relatively new , which performed impressively fast in San Francisco. Apps would download in seconds, and most Webpages loaded almost instantly. Using the Ookla Speed Test app here in PCWorld's San Francisco office, the HTC One X managed to get download speeds of up to 24 megabits per second (mbps), with uploads going out around 9 mbps. This was in an area with a strong data connection, so you'll likely see those numbers change based on how coverage is in your region. Keep in mind that AT&T's LTE network isn't everywhere yet, so not everyone will be able to take advantage of these speeds right away.

Like the , the One X suffered from subpar call quality. While voices on my end came through loud and clear, the people I called said that my voice sounded murky and slightly muffled. They also mentioned that some of my words were randomly dropping out and several times had to ask me what I had just said because one or more words failed to go through. I checked to make sure I had full bars, restarted the phone, and even made sure the SIM card was seated properly, yet the problem persisted. Definitely not something you want to have to deal with in a top-of-the-line handset.

A problem that many smartphones have is poor battery life. Thankfully this was not the case with the One X. After 5 hours of texting, downloading apps, playing games, making phone calls, and browsing the Web over LTE, I managed to knock the battery down to 70 percent. This was with GPS, LTE, and Wi-Fi turned on, and with the screen brightness set to max. While we have yet to conduct our official PCWorld Labs battery tests on the One X, I think most people will be able to make it through an entire day without needing to charge the phone.

Software

The One X comes loaded with Android 4.0.3 (a version of ) and, like most other HTC Android phones, it runs the Sense overlay on top of the standard Android interface. Sense has a variety of stylish and useful widgets, and lets you quickly launch applications directly from the lock screen. The HTC music app has been updated and now acts as a central hub where you can quickly see and start all of the music apps on the phone. The Sense camera app is also noteworthy, as it adds a variety of new shooting modes. I found it vastly superior to the camera app in stock Ice Cream Sandwich.