The high-definition smartphone era is upon us. The HTC Rezound ($299.99) is the first cell phone to hit the U.S. market with a true 720p screen. It's also the first phone with Beats Audio, which promises enhanced sound quality via both software and a matched set of headphones. The Rezound has a few flaws, and it's pricey, but it's a powerhouse smartphone nonetheless.

Design, Connectivity, and Call Quality
The Rezound measures 5.1 by 2.6 by 0.5 inches (HWD) and weighs a hefty 6.0 ounces. It's not thin or light like the Motorola Droid RAZR ($199.99, 4.5 stars), but it's at least a little slimmer than the HTC Thunderbolt ($149.99, 4 stars). The Rezound is mostly black, with a rubberized back panel, and sharp-looking red accents on the earpiece speaker, camera lens, capacitive touch buttons, and Beats logo. HTC arranged the packaging to showcase the included Beats earbuds (more on those later); you also get a little carrying pouch for the earbuds in the box, plus multiple sets of eartips in various sizes.

The 4.3-inch, 1280-by-720-pixel Super LCD display is pretty amazing. At 341 ppi, it's now the densest phone screen available, outpacing the Apple iPhone 4S ($199, 4.5 stars) with its 326-ppi Retina Display. It's also higher resolution than many 7-inch tablets, which are generally 1024-by-600. You'll notice the pixel density in the Web browser and while watching video, but it doesn't jump out at you in other contexts.

While the colors aren't as vivid as what you'll see on Samsung's Super AMOLED Plus displays, it's still plenty bright and colorful. Typing on the screen using HTC's stock keyboard is easy in both portrait and landscape modes.

The Rezound is a dual-band EV-DO Rev. A (850/1900 MHz) and single-band LTE (700MHz) device with 802.11a/b/g/n Wi-Fi. It's not a world phone, as there's no GSM radio. Verizon's fast 4G LTE network, which is now available in 160 cities across the U.S., delivers an average of around 9.5Mbps down according to our 21-city nationwide tests. The Rezound also works as a mobile hotspot for up to 10 Wi-Fi-enabled devices with the appropriate plan. The Rezound connected to my WPA2-encrypted Wi-Fi network without trouble.

Voice quality was okay overall, with a bright, somewhat midrangey tone in the earpiece. I heard a little static around some syllables, but it wasn't bad. There was a ton of gain available; watch the volume control, or you could put your hearing at risk. Transmissions through the mic sounded fine, and reception was good. Calls sounded clear through an Aliph Jawbone Era Bluetooth headset ($129, 4 stars). The voice dialing failed to recognize my commands most of the time, but at least you can trigger it over Bluetooth. The speakerphone was weak, with a thin tone and not nearly enough volume for use outside. The 1620mAh battery ran for an excellent 8 hours and 37 minutes of talk time.

Hardware, Apps, and Audio
The 1.5GHz Qualcomm MSM8660, S3 dual-core processor and 1GB RAM are top-notch hardware. You get Android 2.3.4 (Gingerbread) with the latest version of HTC Sense. You can configure the lock screen to show additional information, and there's a new group messaging feature that works across multiple platforms, but the Rezound still hesitates on occasion as you navigate around the UI. HTC is promising an upgrade to Ice Cream Sandwich for "early 2012," which is further away than I'd like, but at least the prospect is there. The Rezound benchmarked well, but not great; the Droid RAZR and the Samsung Galaxy S II Skyrocket ($249, 4.5 stars) (over on AT&T) both performed as good or better on our various benchmark tests.

That said, browsing the Web on a 720p phone is what you'd expect: awesome. You can fit desktop pages comfortably enough, at least in landscape mode, to view them at full width and still manage to read the text. HTC's own apps are fun to use and integrate social networks well, and Android Market contains over a quarter-million third-party apps. It's possible you'll run into some compatibility issues with apps that can't handle the high-res screen, although I didn't stumble on any during the review period.

For multimedia, there's 12.68GB of free internal storage; HTC also throws in a 16GB SanDisk microSD card, and my 32GB card worked fine. The slot is behind the battery, though; swapping cards requires a reboot.

The Beats Audio headphones—this phone's other star distinction, after the 720p display—look sharp, with their red wires and finely-crafted earbuds. The wires include a little remote control with a mic that answers calls and controls the music player app. You want bass? You get bass, including some serious low-end extension with the Beats Audio software enhancer enabled. I'd call the resulting sound "hi-fi" more than audiophile, because both frequency extremes sound overly boosted—though sometimes that can be a good thing with rock and hip-hop tracks. Without Beats Audio enabled, the headphones by themselves sound more muffled than what you'll hear on a good Shure or Etymotic set. Suffice to say it's an acquired taste.

Music tracks also sounded fine through Samsung Modus HM6450 Bluetooth headphones ($99, 4 stars), for what it's worth, though the Beats Audio enhancer only works with wired earbuds.

Video, Camera, and Conclusions
Standalone videos looked fantastic, especially 720p and 1080p videos, the latter of which the handset transcodes on the fly. It's a treat to watch a 720p video natively on a cell phone. But the video player crashed once during the review, and there's no kickstand, either. HTC's Watch service offers premium movies and TV show rentals using cached streaming, so you can begin watching while the rest of the file downloads in the background. You can also output video through an MHL adapter (not included) to an HDTV, complete with 5.1 surround sound.

The camera and camcorder didn't hold up very well in testing. The 8-megapixel, auto-focus, f/2.2 camera includes a dual-LED flash and a 28mm wide-angle lens with a panoramic mode. Test photos looked good with plenty of light, both indoors and out, but began to fall apart as the sky darkened. Some dusk shots looked blurry and lacked detail, and indoor photos in medium light were pixelated and had a yellowish cast. Recorded 720p and 1080p videos were just okay, with blurred details, some dark areas, and a not-quite-smooth 23 frames per second frame rate average for both resolutions. There's also a 2-megapixel front-facing camera for video chats.

The Rezound supplants the HTC Thunderbolt, as the Rezound has a sharper display, weighs less, features the latest version of HTC Sense, and comes with better headphones, although the Thunderbolt is still a nice smartphone if you want to save $150. The Droid RAZR keeps its Editors' Choice crown, thanks to its slimmer and lighter design, equally brilliant (if lower resolution) display, lower price, and Motorola's comprehensive Webtop ecosystem of accessories, although the Rezound comes with the Beats Audio earbuds and that amazing 720p screen.

We haven't tested the Verizon Wireless version of the Apple iPhone 4S, but if it's like the Sprint version, it offers a superior camera and 1080p camcorder (complete with image stabilization), not to mention the best app store on the planet. But it has a smaller screen and much slower 3G data speeds. And how about the Samsung Galaxy Nexus? That one is just around the corner, with Android 4.0 (Ice Cream Sandwich) and a true 720p display as well; hang on tight for our upcoming review. If you want high-definition video and great quality audio today, the Rezound is a solid choice—just give it another week to see how the Galaxy Nexus turns out.

Benchmarks
Continuous talk time: 8 hours 37 minutes

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