The winter holidays are a special time of the year. Christmas lights are going up on homes, carolers are filling the streets, fireplaces are glowing, and we're taking stock of the best smartphones of 2011. Whether you're planning to purchase one of these amazing devices for yourself or a loved one, Engadget's smartphone buyer's guide is your essential source for selecting a handset that best suits your desires and budget.

No doubt, you've already had an opportunity to review our holiday gift guide for 2011. The smartphone buyer's guide is a bit different. Here, we examine the variety of options from each carrier, large and small, along with its most solid alternatives. Those insistent upon QWERTY keyboards will find each provider's pick of the litter, and we also select a high quality budget offering with $80 as the absolute ceiling. Compared to our previous buyer's guide, Samsung is lighting up the scoreboard more than ever -- largely in part to the Galaxy S II, but that isn't keeping other manufacturers from pushing back. The past 12 months have shown amazing development in the smartphone arena, so join us after the break as we round up the most exciting options of the year.

AT&T

With the Skyrocket, AT&T has taken Samsung's wildly popular Galaxy S II platform and added support for the carrier's nascent -- and quite speedy -- LTE network. In the process, it also bumped up the screen size to 4.5-inches, just like its brethren on Sprint and T-Mobile. With little other meaningful differentiation, we're inclined to recommend the Skyrocket over its Galaxy S II ($200) forebear. If network speed or the modest display increase aren't important, you can certainly feel safe with the standard model and save $50 in the process. Devotees of iOS will be glad to know that Apple's claim is correct: the iPhone 4S ($200 - $400) is easily the best iPhone yet. Although, even with its spectacular camera and Siri integration, we can't help but feel that it's falling behind the curve. Still, if you live and die with the Cupertino crew, we feel that AT&T's iPhone is your best option as it delivers HSPA+ support and allows you to talk and surf the web simultaneously -- unlike its CDMA counterparts found on Sprint and Verizon. Likewise, the HTC Titan ($200) is an extremely impressive handset with a large display that makes typing a breeze, and it packs an excellent camera to boot. As it stands, Windows Phone enthusiasts won't find a more compelling option on any carrier.

If a keyboard is what you're after ...

The Captivate Glide is a new -- and very welcome -- QWERTY addition to AT&T's lineup, which easily replaces the Crossover (free) as the network's best Android device with a physical keyboard. We've yet to properly review the handset, although our early impressions have been mostly positive. We found its keyboard to be rather competent, although its price tag may deter some. In this case, the BlackBerry Torch 9810 ($50) is an attractive alternative, which features excellent voice quality and battery life -- although, some users may find frustration with its comparatively limited app selection.

If you're looking to squeeze every penny...

Sure, it's not the first time we've seen dual-cores go for next to nothing, but picking up the Atrix 4G for a single round Lincoln is a fantastic deal. This powerhouse formerly stood as one of AT&T's premiere handsets, and with good reason -- it features a speedy Tegra 2 SoC and an excellent qHD display. We think you'll be hard-pressed to find more for so little, but the deal won't last, so you might want to jump on this one. We're also happy to see that the Infuse 4G ($50) is now extremely affordable, and some will definitely appreciate its massive 4.5-inch display and gorgeous camera. Whichever you prefer, you'll certainly score one for the bank account.

Sprint

Dare we say it, but Sprint's changes to the Galaxy S II resulted in a device that's even more satisfying than the original. In fact, the Epic 4G Touch may be our favorite of the bunch. We're really digging its gorgeous 4.5-inch display, along with the extra battery life and that handy notification light. It retains the speedy Exynos that we love, and the pictures are excellent. The only omission that may dissuade some buyers is the lack of international support. If this is on your list of "must-haves," then the Photon 4G ($200) remains an extremely good candidate, which offers an unlocked SIM slot for roaming abroad. Naturally, this also presents the iPhone 4S ($200 - $400) as an option, although in this case, we still prefer the faster HSPA+ speeds that you'll enjoy on AT&T's network.

If a keyboard is what you're after ...

We'll be very frank by saying that Sprint should've replaced its venerable Epic 4G by now -- and no, the Transform Ultra ($80) simply isn't going to cut it. As a member of the original Galaxy S family, the Epic 4G has been surpassed by more compelling options from other providers. Even worse, the $100 price now feels somewhat steep. Yes, it was once an excellent device, but this is by yesterday's standards. Now, it's a relatively ho-hum offering that you should consider only as a last resort. Our advice? If you really need a keyboard, either wait for Sprint to get off its laurels or jump ship.

If you're looking to squeeze every penny...

We're sad to report that Sprint has increased the price of the Nexus S 4G -- our former budget pick -- to a full $100, which prohibits its consideration for this category. Fortunately, the Conquer 4G is now available online for free, and surprisingly, it runs pure Android (save for a few customizations from Hesse and crew). While nothing about the phone stands out as particularly high-end, it's easily the best value on the Now Network. All in all, it's a rather solid pick with a price that'll stir at least a modicum of excitement.

T-Mobile

We remain infatuated by the Galaxy S II, and yes, that holds true for T-Mobile as well. Sure, it's not quite as speedy as its siblings, but the phone still offers excellent performance combined with a beautiful display and top-notch camera. Given its status as a 42.2Mbps HSPA+ device, it's an extremely competent performer on T-Mobile's AWS network. Sadly, battery life wasn't quite as good on this variant, although it's still very sufficient. If you're looking for the best that the Galaxy S II lineup has to offer, however, we recommend giving the Skyrocket and Epic 4G Touch a serious consideration.

If a keyboard is what you're after ...

The QWERTY landscape changed a bit at T-Mobile after its launch of the myTouch Q ($80), but certainly not enough to unseat the myTouch 4G Slide. Y'all are aware that it's not the most desirable handset we've come across, which is hindered by its slower than expected performance, mushy keyboard and subpar battery life. When compared to the myTouch Q, however, it's redeemed by the higher-res WVGA display and excellent camera that's accompanied by a dedicated two-stage shutter button. If the uninspired keyboard on the myTouch 4G Slide is a deal-breaker for you, feel free to check out the BlackBerry Torch 9810 ($250) and Bold 9900 ($300) -- although we feel both options are priced too high to warrant a whole-hearted recommendation.

If you're looking to squeeze every penny...

Yes please, and thank you. T-Mobile is running a special online promotion right now where the Radar 4G can be yours for absolutely nothing. If you're not drooling yet, you most definitely should be. Folks, this is one of the finest Windows Phone handsets under the sun today. We were particularly happy with its vibrant display, quality camera and admirable battery life. What's more, it feels excellent to hold and the build quality is rather superb. If you absolutely insist on an Android phone, you'll be glad to know that the myTouch ($80) has significantly stepped up T-Mobile's value offering, which delivers a 1GHz CPU, a 3.8-inch display and HSPA+ connectivity. We're holding back from an unqualified recommendation, however, as we've yet to review the handset.

Verizon Wireless

Although the Galaxy Nexus has yet to arrive at Verizon, it's easy to quantify why this smartphone is the most desirable of the season. As Google's latest halo device, the phone serves as the launchpad for Android 4.0, otherwise known as Ice Cream Sandwich. Yes, the Galaxy Nexus is large, but it's also well-proportioned and houses a massive 720p display that's simply phenomenal. Users won't be at a loss for speed, either, as the phone struts a dual-core 1.2GHz CPU and taps into Verizon's LTE network. While we only recently scored a hands-on with this variant, it promises to knock one out of the ballpark on its road to glory -- absent any unforeseen circumstances, anyway.

If a keyboard is what you're after ...

In our last buyer's guide, we were unable to recommend the Droid 3 based on its poor software implementation and frustrating glitches. Fortunately, those problems have since been resolved with Motorola's most recent round of updates. Now, users may experience this QWERTY slider as the manufacturer intended, which features an excellent keyboard and a handsome qHD display. It can be a bit unwieldy for some, however, and the Bold 9930 ($200) remains a fine option for these individuals, which provides superior battery life and a very attractive (though comparatively small) display.

If you're looking to squeeze every penny...

Verizon Wireless hasn't typically been the friendliest network to value-conscious consumers, but fortunately, its recently announced Illusion just barely makes the cut. What's essentially the Conquer 4G (albeit, without 4G and with TouchWiz), this phone isn't likely to turn heads, but its 1GHz CPU delivers just enough oomph that budget users won't feel completely left behind. Still, unless you rely on Verizon for coverage, the same phone can be found for free on Sprint with added WiMAX support. So, why not?

Boost Mobile

Boost Mobile recently launched the Warp as its flagship phone and, what can we say, we like nice things. For starters, the device holds the distinction of being the carrier's sole handset with a WVGA display, which just so happens to be implemented in a roomy 4.3-inch screen. Also, thanks to its 1GHz processor and near-stock implementation of Gingerbread, our interactions with the phone felt quite nimble. And then there's the price. It's often difficult to find a smartphone that offers so much for so little in the prepaid world, and the Warp is one of the rare few that delivers. Sure, some may be tempted by the name recognition of the Transform Ultra ($230), but unless you need a physical keyboard, its low-resolution HVGA display will leave most users begging for more headroom.

C Spire

When Cellular South renamed itself C Spire Wireless, few could've imagined that the regional carrier would be adding one of the year's hottest and most sought after devices to its mix. This is amazing news for the provider's 900,000 customers, which primarily reside in Mississippi, Memphis and the Florida panhandle. Make no mistake about it, it's hard to go wrong with the latest iPhone. While we'd love to see more diversity in iOS devices, the iPhone 4S is an admirable refresh that provides an upgraded A5 dual-core CPU, along with a brilliant camera and the excellent Retina Display, which has many manufacturers still playing catch-up nearly 18 months after its arrival.

Cincinnati Bell

Thanks to Cincinnati Bell's AWS roots, this regional provider is truly a kindred spirit with T-Mobile. As such, it's sporting variants of some incredibly hot phones that were previously available on the Magenta-clad network: specifically, the Sensation ($200) and G2x ($150). Yes, it's a rematch of T-Mobile's former titans, but you know how the battle ends. We tip our hat to the LG's lovely IPS display, excellent camera and stock Android 2.3 implementation. In truth, both devices are quite excellent, and if you're switching to Cincinnati Bell from another carrier, you can pick up either of them for free. Still, we feel that the Sensation's higher-res qHD display simply isn't enough to undermine our love for the G2x.

Cricket

Cricket's selection of smartphones aren't the most amazing you'll come across, but thanks to its value-driven plans, many customers are willing to forgive the oversight. Leading the pack are the Vitality ($150) and Transfix ($160). Both devices are stunningly similar, save for the Vitality being a member of Cricket's Muve Music lineup and the Transfix adding a physical keyboard to the mix. Which handset you choose will depend on your needs and budget. The Vitality's plan costs $65 per month, which is $10 more than Cricket's standard unlimited offering. Of course, this fee provides access to an all-you-can-eat music subscription service. If you think you'll enjoy the tunes, get the Vitality. Otherwise, direct your mitts toward the Transfix and jam out to all those MP3's you've been hoarding.

MetroPCS

If this Samsung handset seems familiar, it should. The Admire ($100) shares the same heritage as the Vitality and Transfix, and delivers the best combination of performance and value on MetroPCS. Sure, the Esteem ($350) is certainly more powerful, which provides a large display and LTE connectivity, but we were underwhelmed when the device was reviewed as the Revolution, and its price seems most difficult to swallow. Even the Wildfire S ($180) can't justify its cost when compared to the Admire -- unless you're really in need of an LED flash, anyway. Consider this one a victory by default.

US Cellular

Folks, this is what we call a no-contest knockout. There's only one phone to consider from US Cellular right now, and it's the Electrify. This handset is essentially a re-branded version of the Photon 4G, which enjoyed a brief time in the sun as Sprint's flagship device. Sure, there's no WiMAX, but the Electrify shines with its excellent performance, pleasing display and quality camera, along with top-notch battery life. Thankfully, it has even retained its world phone capabilities. There's really only one game in town, so even if you have to pinch pennies for a couple of months, get the Electrify and never look back. It's really as simple as that.

Virgin Mobile

We'd really love to see a few of Sprint's top-tier devices on its value-oriented subsidiary, but that's not to suggest Virgin isn't without some quality handsets up its sleeve. Our current favorite is the Optimus Slider, which we were able to get friendly with during CTIA. Thanks to an 800MHz CPU, this QWERTY slider packs a bit more oomph than the similarly priced Wildfire S ($200), and unlike the Triumph ($300), it doesn't break the bank. If you detest the idea of a physical keyboard, the Optimus V ($130) remains a reliable standby, although we can't help but feel that it's beginning to show its age.

Unlocked phones

If you're looking for something different -- you know, that's not Android or Samsung -- have we got a choice for you. It's the N9, and dare we say you'll be the only one amongst your friends or family with a phone running MeeGo. The handset itself is one of the most lust-worthy slabs of engineering we've ever come across, which packs a beautiful display and excellent camera. We think you'll be impressed with the battery life, too. What's best, this unlocked phone features pentaband 3G support along with quadband GSM. MeeGo may be going the way of the dinosaur, but you can be sure the N9 will have your back.

The Galaxy Nexus is unlikely to be remembered as quite the game changer as the Galaxy S II, but that's not to deny the phone is an amazing piece of kit in its own right. Leading the charge with Ice Cream Sandwich, the Galaxy Nexus holds special notoriety as the first Android handset to include a pentaband HSPA+ radio. This is especially important for its consideration as an unlocked device, which offers 21Mbps support on AT&T, T-Mobile and through the international 2100 / 900MHz bands. Sure, we're a bit disappointed by its middle-of-the-road camera and lack of support for USB Mass Storage, but that's a mere pittance to overlook when compared to the amount of goodness crammed into this beauty.

The Galaxy Note certainly isn't appropriate for everyone, as its massive size will always come across as a bit polarizing. Also, its lack of 3G support for T-Mobile makes it a bit less versatile than the Galaxy Nexus. Still, we're absolutely enamored by this Samsung, thanks to its chart-topping performance and impressive 5.3-inch display. The excellent battery life and top-notch camera are merely additional bonuses when considering this slab can fill the roles of both a smartphone and tablet. Those in the States can access AT&T's HSPA+ network at 21Mbps, along with the 2100 and 900MHz bands when traveling abroad. As it's not currently available from any of the domestic carriers, the Galaxy Note is a surefire way to turn heads and make onlookers weep with jealousy. Can life get any sweeter than that? Editor's note: There are many outlets that sell unlocked phones, but we recommend including Expansys, Negri Electronics and NewEgg in your search. They've always treated us fairly and we're pretty sure they'll do the same for you. Also, it's worth mentioning that Apple is selling unlocked versions of the iPhone 4S ($650 - $850) for the first time in the United States. Good luck in the hunt, everyone!