Editors' note: Portions of this review were taken from our evaluation of the unlocked Samsung Galaxy S II and the Samsung Epic 4G Touch, since the devices share a number of similarities.

The Samsung Galaxy S II is making the carrier rounds, and its next stop is AT&T. Available on October 2 for $199.99 with a two-year contract, the Samsung Captivate successor boasts a faster dual-core processor, sharper display, and better cameras. It more closely resembles the unlocked Galaxy S II than the T-Mobile and Sprint versions, since it features a smaller 4.3-inch touch screen (versus 4.5 inches), but we actually think that's a good thing since it offers a more appealing design. More importantly, the Android Gingerbread device delivers great performance in almost all aspects and earns itself our Editors' Choice Award. If you're an AT&T customer looking for an Android smartphone, the Samsung Galaxy S II would certainly be our top choice.

Design
The Samsung Galaxy S II joins AT&T's lineup as the carrier's thinnest (oh, if only we got a dollar for every time we heard that superlative) 4G smartphone. The handset measures 4.96 inches tall by 2.6 inches wide by 0.35 inch thick--a whole 0.1mm thinner than the Infuse 4G, if you're counting. The difference in thickness is negligible, but still, the Galaxy S II is much easier to hold and pocket since it's not as wide or as tall as the Infuse or the Sprint and T-Mobile versions of the phone.

This is because the AT&T Galaxy S II has a smaller 4.3-inch (versus 4.5 inches) touch screen. Screen size is certainly a personal thing, but we found 4.3 inches to be enough to comfortably view Web pages, video, and messages. Plus, the AMOLED Plus, 800x480-pixel display shows off deep colors and sharp images and text.

The touch screen is responsive. The smartphone offers several virtual keyboards, including Android, Samsung, and Swype. It registered all our taps, and we were able to easily navigate through the menus. In addition to using the standard touch interface, you can also use motion gestures. With the settings turned on, you can flip the phone to mute it. With two fingers on the screen, you can tilt to zoom in and out in the photo gallery and browser. Flicking your wrist left or right (panning) can move a home screen icon when you're holding it. However, panning and zooming weren't as responsive as we'd like. While most of the motion controls may not figure into your daily use, this type of gesture functionality adds welcome options in general. You can also perform certain tasks, such as composing and sending a message, calling a contact, and launching the music player, using voice commands with the Vlingo-powered Voice Talk app.

Below the screen, you'll find the menu, home, back, and search buttons. On the left side, there's a volume rocker and a power/lock button on the right. The top of the device houses a 3.5mm headphone jack, and the bottom features a Micro-USB port.

Just above the screen in the left-hand corner is a 2-megapixel camera for video calls; the main 8-megapixel camera and flash sit on back. The microSD expansion slot is located behind the very flimsy plastic battery door. The latter aside, the Galaxy S II feels nice in the hand, and because of its more manageable size, we think it will be an attractive option for a wider audience than the Infuse 4G or other Galaxy S II models.

AT&T packages the Samsung Galaxy S II with just the basics: an AC adapter, a USB cable, and reference material.

User interface
The Samsung Galaxy S II runs Android 2.3.4 Gingerbread along with Samsung's latest TouchWiz 4.0 user interface. We're often less enthusiastic about custom interfaces; they sometimes add unwanted complexity and unremovable apps, and are usually slower to update to new OS versions. However, TouchWiz 4.0 has a few things going for it: some carryovers from previous versions of TouchWiz. There are seven home screens, for example, and the notification pull-down menu has icons for easily turning on Wi-Fi, Bluetooth, GPS, flight mode, and screen rotation.

Customizing the home screens is made easier with a carousel-like setup that lets you move through the various panels to add and remove shortcuts and widgets at the same time. Previously, you had to do a long-press on one screen to change it and then repeat the process if you wanted to change another page. You can also now resize Samsung Live Panel widgets, and there's a more fluid motion when scrolling through widget lists and home pages.

Some of the changes are purely cosmetic, but they certainly add some polish to the UI. There are also some useful additions as well, such as an integrated task manager that displays all your active applications, downloaded apps with the option to uninstall, RAM status, and system storage. Also great: the ability to now capture screenshots by simply pressing the power button and home key simultaneously.

Features
The quad-band Samsung Galaxy S II offers a speakerphone, conference calling, voice dialing, video calling, and text and multimedia messaging. The smartphone is compatible with AT&T's HSPA+ network and can be used as a mobile hot spot for up to five devices. Bluetooth 3.0, Wi-Fi (802.11a/b/g/n), and GPS are also onboard.

As we noted earlier, it is running Gingerbread and all of Google's services are accounted for: e-mail, maps, voice navigation, search, chat, Places, Latitude, and YouTube, plus basic tools like a calendar, a calculator, an alarm clock, a world clock, a stopwatch, and a timer. In addition, Samsung and AT&T have preloaded the phone with a number of extras, including the Quickoffice suite, Kies Air (a Wi-Fi-based PC-to-phone sync manager), AT&T Navigator, AT&T Code Scanner, and Yellow Pages Mobile. We're not a fan of having so much bloatware on the phone, but thankfully, AT&T now gives you the option to uninstall some of its apps, such as AT&T FamilyMap and Live TV.

There is no shortage of entertainment options on the Galaxy S II. In addition to the built-in music and video player, the smartphone offers Samsung's Media Hub where you can download movies and TV shows to rent or own. You can also shoot your owns videos and photos with the handset's 8-megapixel camera, which is capable of 1080p HD video capture. The camera app has plenty of tools, such as effects, white-balance controls, ISO settings, and more. Samsung also throws in a photo and video editor, which we appreciate. The video editor is particularly great, since it makes it easy to piece together clips with different effects and music, all from right on your phone.

Picture quality was impressive. Even under less-than-ideal lighting conditions, the camera produced bright, detailed, and clear images, and camera performance was fast. Video quality was also very good. Again, colors looked vibrant and there was very little blurring and pixelation, even during action sequences. Once you're done capturing media, you can store files to the Galaxy S II's 16GB of internal memory or to an SD card (expansion slot accepts up to 32GB). You can also share via the usual social network channels or to your HDTV using DLNA or with an HDMI adapter.

Performance
We tested the quad-band Samsung Galaxy S II in New York using AT&T service and call quality was excellent. We enjoyed clear audio with very little to no background noise. Occasionally, callers sounded a bit muffled, but overall, the voices sounded true to life without any kind of distortion. Friends were also impressed with the sound quality and didn't have any major complaints.

Samsung Galaxy S II call quality sample Listen now:

Speakerphone quality wasn't quite as good. Callers said they could hear a bit of an echo, and on our end, they sounded far away and there was barely enough volume to hear them in noisier environments. We were able to pair the smartphone with the Logitech Mobile Traveller Bluetooth headset and Mobile S9 Bluetooth Active Headphones and make calls and listen to music without any problems.

We didn't experience any dropped calls during our review period. Data speeds on AT&T's HSPA+ network, which the carrier calls 4G, were OK, but not a standout compared with competing carriers' 4G networks. Using Ookla's Speedtest.net app, we averaged download speeds of 2.36Mbps and 1.12Mbps up. With such speeds, CNET's full site loaded in 20 seconds, and the mobile sites for CNN and ESPN came up in 5 seconds and 7 seconds, respectively. The phone was able to load and play high-quality YouTube videos in a couple of seconds, and playback was smooth and continuous.

Equipped with Samsung's 1.2GHz dual-core Exnyos processor, general performance on the Galaxy S II was fast and powerful. Navigating the phone was zippy, and we were able to launch apps and switch between tasks with ease. Whether it was playing games or viewing Flash content, the smartphone was up to the challenge.

The Samsung Galaxy S II ships with a 1,650mAh lithium ion battery with a rated talk time of 8 hours and up to 16 days of standby time. The Galaxy S II provided an impressive 10 hours of continuous talk time in ourbattery drain tests. According to FCC radiation tests, the Galaxy S II has a digital SAR rating of 0.36W/kg and a Hearing Aid Compatibility rating of M3.

Conclusion
As we've already seen from the other series models, the Samsung Galaxy S II is an excellent Android smartphone, and it makes for a great addition to AT&T's lineup. The carrier already has a number of other great Android devices, such as the Samsung Infuse 4G, Motorola Atrix 4G, and HTC Inspire 4G, but the Galaxy S II brings the total package of an attractive design, great set of features, and solid performance to make it the top pick and Editors' Choice winner.