The Samsung Nexus S was born to be a pleasant, midrange Android phone. And that's what it's become, nine months into its life, as it finally appears on AT&T: A no-nonsense, affordable, attractive touch-screen smartphone, albeit one without much to propel it past other smartphones. The Nexus S will appeal to Android hackers and developers because it runs stock Android 2.3, rather than a carrier or manufacturer version. That means it's easier for adept users to edit or replace the operating system on the phone, and future Android upgrades will probably come more quickly than they do for other handsets.

Physical Features, Call Quality, and Internet

The AT&T Nexus S uses the same body as T-Mobile's version (4 stars), which debuted last December. At 4.9 by 2.5 by 0.4 inches and 4.5 ounces, the Nexus S is a black slab phone that's noticeably smaller than the recent round of humongo-phones with 4.3-inch screens. The Nexus looks elegant because it uses more rounded corners and a black bezel, rather than cheaper-looking chromed plastic. The 4-inch, 800-by-480 Super AMOLED screen is curved to cradle your face, but, in use, I couldn't feel any difference between it and a perfectly flat screen.

Samsung and AT&T have clearly been working to improve the reception on this phone; I got strong RF reception and excellent voice call quality, better than on the T-Mobile or Sprint models. The earpiece is loud and clear and doesn't distort, and the speakerphone is one of the loudest I've used recently. The down side is on transmissions: on the other side of a call, transmissions sounded oddly scratchy and a bit echoey. The phone had no problem hooking up to my Aliph Jawbone Era Bluetooth headset ($129, 4.5 stars) and activating voice dialing. I got 8 hours, 10 minutes of talk time, which is very good for a 3G phone.

The Nexus S connects to AT&T's network at respectable 3G, HSPA 7.2 speeds. I got around 1500Kbps down and 150Kbps up. That's long been outpaced by HSPA 14.4 and HSPA+ 21 phones, which can get speeds of double or triple that on AT&T's network. The phone also has Bluetooth, Wi-Fi 802.11 b/g/n, and a GPS which (unlike on T-Mobile's version) locked in quickly. NFC wireless technology is built in, and could someday let your phone be used as a digital credit card. But for now, I couldn't even find anywhere in New York City to test NFC.

Android and App Performance
The Nexus S has one killer feature for Android geeks and software developers: it runs an unmolested version of Google's "pure" Android, which hasn't been edited or locked down in any way. For now, that means Android "Gingerbread" 2.3.4. If you're a hacker or software developer, this is your dream phone.

You'd think the "pure" Android version would give the Nexus S a leg up over other phones in benchmarks, but that's not entirely the case. Let's set aside the new crop of dual-core phones and compare the Nexus S to similar single-core, 1GHz devices. We know that Samsung's 1GHz Hummingbird has excellent all-around system performance, and the Nexus S beat similar 1GHz phones like the Qualcomm-based HTC EVO 4G and Motorola Triumph on the all-around Antutu system benchmark as well as GUIMark's Flash tests.

But oddly, that didn't translate into triumphant results on browsing benchmarks; the EVO beat the Nexus S 4G on the Sunspider Javascript test, while the Triumph beat it on the Browsermark test. This phone performs well, just not much better than the competition, and its 1GHz processor is outmatched by higher-end dual-core models nowadays. I found similar results with the previous Nexus S models, where I said, "The UI is faster all around than on Android 2.2 phones, though Web performance isn't."

Many techies fetishize "stock" Android because carrier OS versions drag down performance, but those manufacturer versions have their own strengths. For instance: The touch keyboard on the Nexus S is much smaller than on Motorola and HTC phones, which may cause frustration for folks with clumsier fingers.

Since there are no carrier or manufacturer preloads here, the Nexus S is what you make of it. Android Market, with its 200,000 applications, is open to you, and the Nexus S is compatible with nearly everything. That makes sense, given that the Nexus S is Google's official developer phone.